Allow amparsand (&) in model while Sanitize using HtmlSanitizer C# - c#

I am using the HtmlSanitizer to Sanitize the url as well as the html. When I am passing the & from the UI the Sanitize converts to &
I want to allow the & to be get passed in the model. I used the below code from the api
_sanitizer.AllowedSchemes.Add("&");
complete code
public void SetValue(object target, object value)
{
if (value is string s)
{
_sanitizer.AllowedSchemes.Add("&");
var encodedString = _sanitizer.Sanitize(s);
_targetProperty.SetValue(target, encodedString);
}
else
{
// Shouldn't get here as we checked for string properties before setting this value provider
_targetProperty.SetValue(target, value);
}
}
The above code conver the & to &amp. Is there any way to allow & in the HtmlSanitizer
References
https://github.com/mganss/HtmlSanitizer

Found the solution after the research. Create a custom html mapper
private string Sanitize(string text)
{
return Sanitizer.Sanitize(text, "", NoEntityMarkupFormatter.Instance);
}
private class NullEntityResolver : IEntityProvider
{
public string GetSymbol(string name)
{
return null;
}
}
private class NoEntityMarkupFormatter : IMarkupFormatter
{
internal static readonly NoEntityMarkupFormatter Instance = new NoEntityMarkupFormatter();
private static readonly IMarkupFormatter defaultFormatter = HtmlMarkupFormatter.Instance;
public string Text(string text)
{
StringBuilder sb = new StringBuilder();
for (int i = 0; i < text.Length; i++)
switch (text[i])
{
// Change: Don't do this as we aren't decoding incoming entities
// case '&': sb.Append("&"); break;
case '\xA0': sb.Append(" "); break;
case '>': sb.Append(">"); break;
case '<': sb.Append("<"); break;
default: sb.Append(text[i]); break;
}
return sb.ToString();
}
public string Comment(IComment comment)
{
return defaultFormatter.Comment(comment);
}
public string Processing(IProcessingInstruction processing)
{
return defaultFormatter.Processing(processing);
}
public string Doctype(IDocumentType doctype)
{
return defaultFormatter.Doctype(doctype);
}
public string OpenTag(IElement element, bool selfClosing)
{
var sb = new StringBuilder();
sb.Append('<');
if (!string.IsNullOrEmpty(element.Prefix))
sb.Append(element.Prefix).Append(':');
sb.Append(element.LocalName);
foreach (var attribute in element.Attributes)
sb.Append(" ").Append(Instance.Attribute(attribute));
sb.Append('>');
return sb.ToString();
}
public string CloseTag(IElement element, bool selfClosing)
{
return defaultFormatter.CloseTag(element, selfClosing);
}
public string Attribute(IAttr attr)
{
var namespaceUri = attr.NamespaceUri;
var localName = attr.LocalName;
var value = attr.Value;
var sb = new StringBuilder();
if (string.IsNullOrEmpty(namespaceUri))
sb.Append(localName);
else if (Is(namespaceUri, NamespaceNames.XmlUri))
sb.Append(NamespaceNames.XmlPrefix).Append(':').Append(localName);
else if (Is(namespaceUri, NamespaceNames.XLinkUri))
sb.Append(NamespaceNames.XLinkPrefix).Append(':').Append(localName);
else if (Is(namespaceUri, NamespaceNames.XmlNsUri))
sb.Append(XmlNamespaceLocalName(localName));
else
sb.Append(attr.Name);
sb.Append('=').Append('"');
for (var i = 0; i < value.Length; i++)
switch (value[i])
{
// Change: Don't do this as we aren't decoding incoming entities
// case '&': temp.Append("&"); break;
case '\xA0': sb.Append(" "); break;
case '"': sb.Append("""); break;
default: sb.Append(value[i]); break;
}
return sb.Append('"').ToString();
}
private static bool Is(string a, string b)
{
return string.Equals(a, b, StringComparison.Ordinal);
}
private static string XmlNamespaceLocalName(string name)
{
return Is(name, NamespaceNames.XmlNsPrefix) ? name : string.Concat(NamespaceNames.XmlNsPrefix, ":");
}
}
private static readonly Configuration TextWithoutEntityConfiguration =
new Configuration().WithCss(e => e.Options = new CssParserOptions
{
IsIncludingUnknownDeclarations = true,
IsIncludingUnknownRules = true,
IsToleratingInvalidConstraints = true,
IsToleratingInvalidValues = true
}).With(new NullEntityResolver());
private static readonly HtmlSanitizer Sanitizer = new HtmlSanitizer
{
HtmlParserFactory = () => new HtmlParser(TextWithoutEntityConfiguration)
};
Reference
https://gist.github.com/nallar/d91160cd6a30b15ccb5265677f0cf29a

Related

How to unflatten flattened json in C#

from this Answer I learned how to flatten a JSON object in c#.
from JSON String:
{"menu": {
"id": "file",
"value": "File",
"popup": {
"menuitem": [
{"value": "New", "onclick": "CreateNewDoc()"},
{"value": "Open", "onclick": "OpenDoc()"},
{"value": "Close", "onclick": "CloseDoc()"}
]
}
}}
To:
The following are lines of strings, not an object
menu.id:file
menu.value:File
menu.popup.menuitem[0].value:New
menu.popup.menuitem[0].onclick:CreateNewDoc()
menu.popup.menuitem[1].value:Open
menu.popup.menuitem[1].onclick:OpenDoc()
menu.popup.menuitem[2].value:Close
menu.popup.menuitem[2].onclick:CloseDoc()
Now, i want to reverse the process.
I can found implementations from this question but it is in JavaScript.
How do I unflatten (return structured JSON from lines) it in C# with json.net?
I managed to solve it out.
Below is my code combined with Sarath Rachuri's flattening code.
I did not test it in too many cases, so it could be buggy.
using Newtonsoft.Json.Linq;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text.RegularExpressions;
namespace JSONHelper
{
class JSONFlattener
{
private enum JSONType{
OBJECT, ARRAY
}
public static Dictionary<string, string> Flatten(JObject jsonObject)
{
IEnumerable<JToken> jTokens = jsonObject.Descendants().Where(p => p.Count() == 0);
Dictionary<string, string> results = jTokens.Aggregate(new Dictionary<string, string>(), (properties, jToken) =>
{
properties.Add(jToken.Path, jToken.ToString());
return properties;
});
return results;
}
public static JObject Unflatten(IDictionary<string, string> keyValues)
{
JContainer result = null;
JsonMergeSettings setting = new JsonMergeSettings();
setting.MergeArrayHandling = MergeArrayHandling.Merge;
foreach (var pathValue in keyValues)
{
if (result == null)
{
result = UnflatenSingle(pathValue);
}
else
{
result.Merge(UnflatenSingle(pathValue), setting);
}
}
return result as JObject;
}
private static JContainer UnflatenSingle(KeyValuePair<string, string> keyValue)
{
string path = keyValue.Key;
string value = keyValue.Value;
var pathSegments = SplitPath(path);
JContainer lastItem = null;
//build from leaf to root
foreach (var pathSegment in pathSegments.Reverse())
{
var type = GetJSONType(pathSegment);
switch (type)
{
case JSONType.OBJECT:
var obj = new JObject();
if (null == lastItem)
{
obj.Add(pathSegment,value);
}
else
{
obj.Add(pathSegment,lastItem);
}
lastItem = obj;
break;
case JSONType.ARRAY:
var array = new JArray();
int index = GetArrayIndex(pathSegment);
array = FillEmpty(array, index);
if (lastItem == null)
{
array[index] = value;
}
else
{
array[index] = lastItem;
}
lastItem = array;
break;
}
}
return lastItem;
}
public static IList<string> SplitPath(string path){
IList<string> result = new List<string>();
Regex reg = new Regex(#"(?!\.)([^. ^\[\]]+)|(?!\[)(\d+)(?=\])");
foreach (Match match in reg.Matches(path))
{
result.Add(match.Value);
}
return result;
}
private static JArray FillEmpty(JArray array, int index)
{
for (int i = 0; i <= index; i++)
{
array.Add(null);
}
return array;
}
private static JSONType GetJSONType(string pathSegment)
{
int x;
return int.TryParse(pathSegment, out x) ? JSONType.ARRAY : JSONType.OBJECT;
}
private static int GetArrayIndex(string pathSegment)
{
int result;
if (int.TryParse(pathSegment, out result))
{
return result;
}
throw new Exception("Unable to parse array index: " + pathSegment);
}
}
}
Purely System.Text.Json solution for unflatteing JSON. Requires .Net 6.
private static JsonNode Unflatten(Dictionary<string, JsonValue> source)
{
var regex = new System.Text.RegularExpressions.Regex(#"(?!\.)([^. ^\[\]]+)|(?!\[)(\d+)(?=\])");
JsonNode node = JsonNode.Parse("{}");
foreach (var keyValue in source)
{
var pathSegments = regex.Matches(keyValue.Key).Select(m => m.Value).ToArray();
for (int i = 0; i < pathSegments.Length; i++)
{
var currentSegmentType = GetSegmentKind(pathSegments[i]);
if (currentSegmentType == JsonValueKind.Object)
{
if (node[pathSegments[i]] == null)
{
if (pathSegments[i] == pathSegments[pathSegments.Length - 1])
{
node[pathSegments[i]] = keyValue.Value;
node = node.Root;
}
else
{
var nextSegmentType = GetSegmentKind(pathSegments[i + 1]);
if (nextSegmentType == JsonValueKind.Object)
{
node[pathSegments[i]] = JsonNode.Parse("{}");
}
else
{
node[pathSegments[i]] = JsonNode.Parse("[]");
}
node = node[pathSegments[i]];
}
}
else
{
node = node[pathSegments[i]];
}
}
else
{
if (!int.TryParse(pathSegments[i], out int index))
{
throw new Exception("Cannot parse index");
}
while (node.AsArray().Count - 1 < index)
{
node.AsArray().Add(null);
}
if (i == pathSegments.Length - 1)
{
node[index] = keyValue.Value;
node = node.Root;
}
else
{
if (node[index] == null)
{
var nextSegmentType = GetSegmentKind(pathSegments[i + 1]);
if (nextSegmentType == JsonValueKind.Object)
{
node[index] = JsonNode.Parse("{}");
}
else
{
node[index] = JsonNode.Parse("[]");
}
}
node = node[index];
}
}
}
}
return node;
}
private static JsonValueKind GetSegmentKind(string pathSegment) =>
int.TryParse(pathSegment, out _) ? JsonValueKind.Array : JsonValueKind.Object;
To flatten a JSON object:
arrayJSON.stringify()

Display data to Debug Console

I writing app for UWP
I have this code
var p = await wc.GetProducts(new Dictionary<string, string>() {
{ "orderby", "id" }, { "filter[search]", "1884" }
});
I try to display data from dictionary like this.
Debug.WriteLine("There");
Debug.WriteLine(p.products);
But it not works.
How I can display data of dictionary ?
Which type does GetProducts() return?
If it's just a Dictionary you can do the following:
foreach(var key in p.Keys)
{
Debug.WriteLine(key);
}
To read a Dictionary --
foreach(KeyValuePair<string,string> kvp in p){
Console.WriteLine(kvp.Key);
Console.WriteLine(kvp.Value);
}
foreach(string key in p.Keys){
Console.WriteLine(key);
Console.WriteLine(p[key]);//value
}
foreach(string value in p.Values){
Console.WriteLine(value);
}
But your problem is that P is a class called products:
Product p = new Product()
{
name = "test product 8",
title = "test product 8",
description = "test product 8",
price = 8.0M
};
You would access the properties of p like:
p.name;
p.title;
p.description;
p.price;
Debug.WriteLine(p.name);
Debug.WriteLine(p.title);//etc
Using the below extension class (Requires Newtonsoft JSON library) you can get a JSON string of any object either with or without readable formatting.
Using the class to get a readable JSON string;
var p = await wc.GetProducts(new Dictionary<string, string>() {
{ "orderby", "id" }, { "filter[search]", "1884" }
});
var jsonString = p.ToFormattedJsonString();
Debug.WriteLine(jsonString);
Using the class to get a plain JSON string without format;
var p = await wc.GetProducts(new Dictionary<string, string>() {
{ "orderby", "id" }, { "filter[search]", "1884" }
});
var jsonString = p.ToJsonString();
Debug.WriteLine(jsonString);
You can also simplfy the above by adding your own extension method such as the below;
public static void ToDebug(this object data)
{
Debug.WriteLine(data.ToFormattedJsonString());
}
The extension class;
using System.Text;
using Newtonsoft.Json;
namespace System
{
public static class JsonExtensions
{
public static string ToFormattedJsonString(this object obj, bool indentWithTab)
{
return indentWithTab
? ToFormattedJsonString(obj, "\t")
: ToFormattedJsonString(obj);
}
public static string ToFormattedJsonString(this object obj, string indentString = " ")
{
return FormatJson(obj.ToJsonString(), indentString);
}
public static string ToJsonString(this object obj)
{
return JsonConvert.SerializeObject(obj);
}
public static T DeserializeJsonString<T>(this string jsonString)
{
return JsonConvert.DeserializeObject<T>(jsonString);
}
private static string FormatJson(string jsonString, string indentString)
{
var indent = 0;
var quoted = false;
var builder = new StringBuilder();
for (var i = 0; i < jsonString.Length; i++)
{
var character = jsonString[i];
switch (character)
{
case '{':
case '[':
builder.Append(character);
if (!quoted)
{
builder.AppendLine();
builder.RepeatAppend(++indent, indentString);
}
break;
case '}':
case ']':
if (!quoted)
{
builder.AppendLine();
builder.RepeatAppend(--indent, indentString);
}
builder.Append(character);
break;
case '"':
builder.Append(character);
bool escaped = false;
var index = i;
while (index > 0 && jsonString[--index] == '\\')
escaped = !escaped;
if (!escaped)
quoted = !quoted;
break;
case ',':
builder.Append(character);
if (!quoted)
{
builder.AppendLine();
builder.RepeatAppend(indent, indentString);
}
break;
case ':':
builder.Append(character);
if (!quoted)
builder.Append(" ");
break;
default:
builder.Append(character);
break;
}
}
return builder.ToString();
}
public static StringBuilder RepeatAppend(this StringBuilder builder, int count, string format,
params object[] parameters)
{
if (count <= 0 || string.IsNullOrEmpty(format))
return builder;
for (int i = 0; i < count; i++)
{
builder.AppendFormat(format, parameters);
}
return builder;
}
}
}

creating new element will delete first element in a list in C#

I have made a class -WhiteList - that contains data which is read from an xml file. I want to make a list of these elements, but after the first element is added to the list, I create a new element for data which erases the contens of the first element in the list. I.E. It seems that the new (elements) re-creates a reference to the element in the list.
Code snippet:
namespace WhiteList
{
public class WhiteListElement
{
private const byte EQL = 0;
private const byte CTN = 1;
private const byte COMMON_NAME = 0;
private const byte ORG = 1;
private const byte ORG_UNIT = 2;
private const byte LOC = 3;
private const byte STATE = 4;
private const byte COUNTRY = 5;
private static string[,] Subject;
private static string[,] Issuer;
private static string MinTlsLevel;
private static string Customer;
public WhiteListElement()
{
Subject = new string[6, 2];
Issuer = new string[6, 2];
Customer = "";
MinTlsLevel = "";
}
//---- set/get functions ---- example
public string GetCommonName(bool SubjectVal, bool Name)
{
if (true == SubjectVal) { if (true == Name) return Subject[COMMON_NAME, 0]; else return Subject[COMMON_NAME, 1]; }
else { if (true == Name) return Issuer[COMMON_NAME, 0]; else return Issuer[COMMON_NAME, 1]; }
}
public void SetCommonName(bool SubjectVal, bool Name, string NewValue)
{
if (true == SubjectVal) { if (true == Name) Subject[COMMON_NAME, 0] = NewValue; else Subject[COMMON_NAME, 1] = NewValue; }
else { if (true == Name) Issuer[COMMON_NAME, 0] = NewValue; else Issuer[COMMON_NAME, 1] = NewValue; }
}
}
class Program
{
public static void CreateWhiteList()
{
try
{
using (XmlReader reader = XmlReader.Create("WhiteList.xml"))
{
while (reader.Read())
{
if (reader.NodeType == XmlNodeType.Element)
{
if (reader.Name == "Kunder")
{
while (reader.Read())
{
if (reader.NodeType == XmlNodeType.Element)
{
XElement el = (XElement)XNode.ReadFrom(reader);
if (el != null)
{
WhiteListElement elem = new WhiteListElement();
var noderef = el.FirstNode;
elem.SetCustomer(el.Name.ToString());
while (noderef.NextNode != null)
{
noderef = noderef.NextNode;
string nodestring = noderef.ToString();
if (nodestring[0] == '<')
{
int startindx, stopindx;
string tag = nodestring.Substring(3);
string data;
tag = tag.Substring(0, tag.IndexOf('_'));
startindx = nodestring.IndexOf('\"') + 1;
stopindx = (nodestring.Substring(startindx)).IndexOf('\"');
data = nodestring.Substring(startindx, stopindx);
switch (tag)
{
case "CERTLVL": elem.SetCertLvl(data); break;
case "CN": if (nodestring[1] == 'S') elem.SetCommonName(true, true, data); if (nodestring[1] == 'I') elem.SetCommonName(false, true, data); break;
case "OU": if (nodestring[1] == 'S') elem.SetOrgUnit(true, true, data); if (nodestring[1] == 'I') elem.SetOrgUnit(false, true, data); break;
case "O": if (nodestring[1] == 'S') elem.SetOrg(true, true, data); if (nodestring[1] == 'I') elem.SetOrg(false, true, data); break;
case "L": if (nodestring[1] == 'S') elem.SetLocation(true, true, data); if (nodestring[1] == 'I') elem.SetLocation(false, true, data); break;
case "S": if (nodestring[1] == 'S') elem.SetState(true, true, data); if (nodestring[1] == 'I') elem.SetState(false, true, data); break;
case "C": if (nodestring[1] == 'S') elem.SetCountry(true, true, data); if (nodestring[1] == 'I') elem.SetCountry(false, true, data); break;
}
}
}
CustomerList.Add(elem);
}
}
}
}
}
}
}
}
catch (Exception ex) { Console.WriteLine(ex.Message); throw (ex); }
}
public static List<WhiteListElement>CustomerList = null;
static void Main(string[] args)
{
CustomerList = new List<WhiteListElement>();
CreateWhiteList();
}
}
}
------------- Code snippet end.
The problem occur after the first element is put in the list (CustomerList.Add(elem)) and returns to the line "WhiteListElement elem = new WhiteListElement();". This will delete the elements in CustomerList[0] and when putting data into elem afterwards, it is inserted into both elem and CustomerList[0], ending up with two identical elements in the list.
I have even tried to put an elem = null after adding elem just to try to erase the reference, but that didn't work
What am I doing wrong?
/Karsten
private static string[,] Subject;
private static string[,] Issuer;
private static string MinTlsLevel;
private static string Customer;
your problem come from here, static members are shared through all instances of a class thus when you edit the second , you erase the first, your class should be like this
public class WhiteListElement
{
private const byte EQL = 0;
private const byte CTN = 1;
private const byte COMMON_NAME = 0;
private const byte ORG = 1;
private const byte ORG_UNIT = 2;
private const byte LOC = 3;
private const byte STATE = 4;
private const byte COUNTRY = 5;
private string[,] Subject;
private string[,] Issuer;
private string MinTlsLevel;
private string Customer;
public WhiteListElement()
{
Subject = new string[6, 2];
Issuer = new string[6, 2];
Customer = "";
MinTlsLevel = "";
}
//---- set/get functions ---- example
public string GetCommonName(bool SubjectVal, bool Name)
{
if (true == SubjectVal) { if (true == Name) return Subject[COMMON_NAME, 0]; else return Subject[COMMON_NAME, 1]; }
else { if (true == Name) return Issuer[COMMON_NAME, 0]; else return Issuer[COMMON_NAME, 1]; }
}
public void SetCommonName(bool SubjectVal, bool Name, string NewValue)
{
if (true == SubjectVal) { if (true == Name) Subject[COMMON_NAME, 0] = NewValue; else Subject[COMMON_NAME, 1] = NewValue; }
else { if (true == Name) Issuer[COMMON_NAME, 0] = NewValue; else Issuer[COMMON_NAME, 1] = NewValue; }
}
}
edit : you can read more on static in the reference : https://msdn.microsoft.com/fr-fr/library/98f28cdx.aspx
especially:
While an instance of a class contains a separate copy of all instance fields of the class, there is only one copy of each static field.
It is not possible to use this to reference static methods or property accessors.
Firstly I think Boo's answer solves your problem, but I thought I would at least suggest a more object orientated approach that might make working with / debugging this problem easier in the future:
public class WhiteListElement
{
public string CertLevel;
public static WhiteListElement Create(XElement xml)
{
WhiteListElement element = new WhiteListElement();
element.CertLevel = xml.Attribute("CERTLVL").Value;
// Put data into object...
return element;
}
}
public class WhiteList
{
public List<WhiteListElement> Elements = new List<WhiteListElement>();
public static WhiteList Create(string xmlUri)
{
WhiteList whiteList = new WhiteList();
whiteList.Elements.AddRange(XElement.Load(xmlUri).Descendants("Kunder")
.Where(xmlElement => xmlElement != null)
.Select(xmlElement => WhiteListElement.Create(xmlElement)));
return whiteList;
}
}
Which can be used as:
WhiteList list = WhiteList.Create("WhiteList.xml");
string certLevel1 = list.Elements[0].CertLevel;
With the example XML:
<Title>
<Kunder CERTLVL="123"></Kunder>
<Kunder CERTLVL="456"></Kunder>
</Title >

How to access a dynamic object's property dynamically (by variable)?

I have a class named Configurationwhich inherits from DynamicObject. It it a Dictionary<string, object>. In the constructor, it reads a text file and loads all the values from it splitted by =, so you can create dynamic configuration objects like this:
dynamic configuration = new Configuration("some_file.ini");
Here is my full class:
public sealed class Configuration : DynamicObject
{
private string Path { get; set; }
private Dictionary<string, object> Dictionary { get; set; }
public Configuration(string fileName)
{
this.Path = fileName;
this.Dictionary = new Dictionary<string, object>();
this.Populate();
}
~Configuration()
{
if (this.Dictionary != null)
{
this.Dictionary.Clear();
}
}
private void Populate()
{
using (StreamReader reader = new StreamReader(this.Path))
{
string line;
string currentSection = string.Empty;
while ((line = reader.ReadLine()) != null)
{
if (string.IsNullOrWhiteSpace(line))
{
continue;
}
if (line.StartsWith("[") && line.EndsWith("]"))
{
currentSection = line.Trim('[', ']');
}
else if (line.Contains("="))
{
this.Dictionary.Add(string.Format("{0}{1}{2}",
currentSection,
(currentSection != string.Empty) ? "_" : string.Empty,
line.Split('=')[0].Trim()),
ParseValue(line.Split('=')[1].Trim().Split(';')[0]));
}
}
}
}
private object ParseValue(string value)
{
if (string.IsNullOrWhiteSpace(value))
return string.Empty;
if (value.StartsWith("\"") && value.EndsWith("\""))
return value.Substring(1, value.Length - 1);
if (IsNumeric(value))
return Convert.ToInt32(value);
// TODO: FIXME Floating values (not to be confuse with IPAddress).
//if (IsFloating(value))
// return Convert.ToDouble(value);
if (string.Compare(value, "true", StringComparison.OrdinalIgnoreCase) == 0)
return true;
if (string.Compare(value, "false", StringComparison.OrdinalIgnoreCase) == 0)
return false;
return value;
}
public override bool TryGetMember(GetMemberBinder binder, out object result)
{
if (this.Dictionary.ContainsKey(binder.Name))
{
if (this.Dictionary[binder.Name] == null)
{
result = null;
}
else
{
result = this.Dictionary[binder.Name];
}
return true;
}
throw new ConfigurationException(binder.Name);
}
public override string ToString()
{
string result = this.Path + " [ ";
int processed = 0;
foreach (KeyValuePair<string, object> value in this.Dictionary)
{
result += value.Key;
processed++;
if (processed < this.Dictionary.Count)
{
result += ", ";
}
}
result += " ]";
return result;
}
private static bool IsNumeric(string value)
{
foreach (char c in value)
if (!char.IsDigit(c))
return false;
return true;
}
private static bool IsFloating(string value)
{
foreach (char c in value)
if (!char.IsDigit(c) && c != '.')
return false;
return true;
}
private class NullObject { }
}
Everything is working flawlessly. I've overriden TryGetMember and I'm returning the object based on the GetMemberBinder Name property. However, I'm facing a problem.
When I execute the following code:
string s = "some_config_key";
string d = configuration.s;
It retrieves the value of the key s rather than some_config_key, meaning that it doesn't evalute the value of the variable s. Is there a workaround for this?
Thanks.
C# dynamic features are partially compiled like the property/method access. To understand this lets take an example.
dynamic myVar = new { a=1, b="test" };
myVar.a += 1;
Here the C# type system would not test for the validity of the property while compilation, only at runtime the code is executed and if the property is not found it will through you runtime error.
So in your code the property access is already complied to access the property named "s" on the dynamic object "configuration".
In C# no-way you can do this not even in dynamically typed languages like python or javascript.
You have to use like this.
dynamic configuration = getConfig("path/to/file");
var myobj = configuration as IDictionary<string,object>;
string s = "config_key";
var value = myobj[s]; // this is correct.

Parsing JSON using Json.net

I'm trying to parse some JSON using the JSon.Net library. The documentation seems a little sparse and I'm confused as to how to accomplish what I need. Here is the format for the JSON I need to parse through.
{
"displayFieldName" : "OBJECT_NAME",
"fieldAliases" : {
"OBJECT_NAME" : "OBJECT_NAME",
"OBJECT_TYPE" : "OBJECT_TYPE"
},
"positionType" : "point",
"reference" : {
"id" : 1111
},
"objects" : [ {
"attributes" : {
"OBJECT_NAME" : "test name",
"OBJECT_TYPE" : "test type"
},
"position" : {
"x" : 5,
"y" : 7
}
} ]
}
The only data I really need from this is the stuff in the objects array. Is it possible for me to parse through that with something like the JSonTextReader and just pull out the things I want, like OBJECT_TYPE and the x and y position? I can't seem to get JSonTextReader to work the way I want it to and I find little to no examples of usage for it.
It seems like serializing first then using LINQ with my object would be ideal and every example I find discusses serializing the JSON first, but I'm not sure how I would build an object for this structure. Particularly the objects array which would need to be something like a list of Pairs of attribute and position objects. I have no idea how I would code my object so JSon.Net would know how to serialize that.
I thought I could write my own simple parser to just pull out everything I need into an attributes object that I created, but I'm having little luck.
Hopefully this all makes sense, any ideas?
I don't know about JSON.NET, but it works fine with JavaScriptSerializer from System.Web.Extensions.dll (.NET 3.5 SP1):
using System.Collections.Generic;
using System.Web.Script.Serialization;
public class NameTypePair
{
public string OBJECT_NAME { get; set; }
public string OBJECT_TYPE { get; set; }
}
public enum PositionType { none, point }
public class Ref
{
public int id { get; set; }
}
public class SubObject
{
public NameTypePair attributes { get; set; }
public Position position { get; set; }
}
public class Position
{
public int x { get; set; }
public int y { get; set; }
}
public class Foo
{
public Foo() { objects = new List<SubObject>(); }
public string displayFieldName { get; set; }
public NameTypePair fieldAliases { get; set; }
public PositionType positionType { get; set; }
public Ref reference { get; set; }
public List<SubObject> objects { get; set; }
}
static class Program
{
const string json = #"{
""displayFieldName"" : ""OBJECT_NAME"",
""fieldAliases"" : {
""OBJECT_NAME"" : ""OBJECT_NAME"",
""OBJECT_TYPE"" : ""OBJECT_TYPE""
},
""positionType"" : ""point"",
""reference"" : {
""id"" : 1111
},
""objects"" : [
{
""attributes"" : {
""OBJECT_NAME"" : ""test name"",
""OBJECT_TYPE"" : ""test type""
},
""position"" :
{
""x"" : 5,
""y"" : 7
}
}
]
}";
static void Main()
{
JavaScriptSerializer ser = new JavaScriptSerializer();
Foo foo = ser.Deserialize<Foo>(json);
}
}
Edit:
Json.NET works using the same JSON and classes.
Foo foo = JsonConvert.DeserializeObject<Foo>(json);
Link: Serializing and Deserializing JSON with Json.NET
Edit: Thanks Marc, read up on the struct vs class issue and you're right, thank you!
I tend to use the following method for doing what you describe, using a static method of JSon.Net:
MyObject deserializedObject = JsonConvert.DeserializeObject<MyObject>(json);
Link: Serializing and Deserializing JSON with Json.NET
For the Objects list, may I suggest using generic lists out made out of your own small class containing attributes and position class. You can use the Point struct in System.Drawing (System.Drawing.Point or System.Drawing.PointF for floating point numbers) for you X and Y.
After object creation it's much easier to get the data you're after vs. the text parsing you're otherwise looking at.
(This question came up high on a search engine result, but I ended up using a different approach. Adding an answer to this old question in case other people with similar questions read this)
You can solve this with Json.Net and make an extension method to handle the items you want to loop:
public static Tuple<string, int, int> ToTuple(this JToken token)
{
var type = token["attributes"]["OBJECT_TYPE"].ToString();
var x = token["position"]["x"].Value<int>();
var y = token["position"]["y"].Value<int>();
return new Tuple<string, int, int>(type, x, y);
}
And then access the data like this: (scenario: writing to console):
var tuples = JObject.Parse(myJsonString)["objects"].Select(item => item.ToTuple()).ToList();
tuples.ForEach(t => Console.WriteLine("{0}: ({1},{2})", t.Item1, t.Item2, t.Item3));
/*
* This method takes in JSON in the form returned by javascript's
* JSON.stringify(Object) and returns a string->string dictionary.
* This method may be of use when the format of the json is unknown.
* You can modify the delimiters, etc pretty easily in the source
* (sorry I didn't abstract it--I have a very specific use).
*/
public static Dictionary<string, string> jsonParse(string rawjson)
{
Dictionary<string, string> outdict = new Dictionary<string, string>();
StringBuilder keybufferbuilder = new StringBuilder();
StringBuilder valuebufferbuilder = new StringBuilder();
StringReader bufferreader = new StringReader(rawjson);
int s = 0;
bool reading = false;
bool inside_string = false;
bool reading_value = false;
//break at end (returns -1)
while (s >= 0)
{
s = bufferreader.Read();
//opening of json
if (!reading)
{
if ((char)s == '{' && !inside_string && !reading) reading = true;
continue;
}
else
{
//if we find a quote and we are not yet inside a string, advance and get inside
if (!inside_string)
{
//read past the quote
if ((char)s == '\"') inside_string = true;
continue;
}
if (inside_string)
{
//if we reached the end of the string
if ((char)s == '\"')
{
inside_string = false;
s = bufferreader.Read(); //advance pointer
if ((char)s == ':')
{
reading_value = true;
continue;
}
if (reading_value && (char)s == ',')
{
//we know we just ended the line, so put itin our dictionary
if (!outdict.ContainsKey(keybufferbuilder.ToString())) outdict.Add(keybufferbuilder.ToString(), valuebufferbuilder.ToString());
//and clear the buffers
keybufferbuilder.Clear();
valuebufferbuilder.Clear();
reading_value = false;
}
if (reading_value && (char)s == '}')
{
//we know we just ended the line, so put itin our dictionary
if (!outdict.ContainsKey(keybufferbuilder.ToString())) outdict.Add(keybufferbuilder.ToString(), valuebufferbuilder.ToString());
//and clear the buffers
keybufferbuilder.Clear();
valuebufferbuilder.Clear();
reading_value = false;
reading = false;
break;
}
}
else
{
if (reading_value)
{
valuebufferbuilder.Append((char)s);
continue;
}
else
{
keybufferbuilder.Append((char)s);
continue;
}
}
}
else
{
switch ((char)s)
{
case ':':
reading_value = true;
break;
default:
if (reading_value)
{
valuebufferbuilder.Append((char)s);
}
else
{
keybufferbuilder.Append((char)s);
}
break;
}
}
}
}
return outdict;
}
You use the JSON class and then call the GetData() function.
/// <summary>
/// This class encodes and decodes JSON strings.
/// Spec. details, see http://www.json.org/
///
/// JSON uses Arrays and Objects. These correspond here to the datatypes ArrayList and Hashtable.
/// All numbers are parsed to doubles.
/// </summary>
using System;
using System.Collections;
using System.Globalization;
using System.Text;
public class JSON
{
public const int TOKEN_NONE = 0;
public const int TOKEN_CURLY_OPEN = 1;
public const int TOKEN_CURLY_CLOSE = 2;
public const int TOKEN_SQUARED_OPEN = 3;
public const int TOKEN_SQUARED_CLOSE = 4;
public const int TOKEN_COLON = 5;
public const int TOKEN_COMMA = 6;
public const int TOKEN_STRING = 7;
public const int TOKEN_NUMBER = 8;
public const int TOKEN_TRUE = 9;
public const int TOKEN_FALSE = 10;
public const int TOKEN_NULL = 11;
private const int BUILDER_CAPACITY = 2000;
/// <summary>
/// Parses the string json into a value
/// </summary>
/// <param name="json">A JSON string.</param>
/// <returns>An ArrayList, a Hashtable, a double, a string, null, true, or false</returns>
public static object JsonDecode(string json)
{
bool success = true;
return JsonDecode(json, ref success);
}
/// <summary>
/// Parses the string json into a value; and fills 'success' with the successfullness of the parse.
/// </summary>
/// <param name="json">A JSON string.</param>
/// <param name="success">Successful parse?</param>
/// <returns>An ArrayList, a Hashtable, a double, a string, null, true, or false</returns>
public static object JsonDecode(string json, ref bool success)
{
success = true;
if (json != null) {
char[] charArray = json.ToCharArray();
int index = 0;
object value = ParseValue(charArray, ref index, ref success);
return value;
} else {
return null;
}
}
/// <summary>
/// Converts a Hashtable / ArrayList object into a JSON string
/// </summary>
/// <param name="json">A Hashtable / ArrayList</param>
/// <returns>A JSON encoded string, or null if object 'json' is not serializable</returns>
public static string JsonEncode(object json)
{
StringBuilder builder = new StringBuilder(BUILDER_CAPACITY);
bool success = SerializeValue(json, builder);
return (success ? builder.ToString() : null);
}
protected static Hashtable ParseObject(char[] json, ref int index, ref bool success)
{
Hashtable table = new Hashtable();
int token;
// {
NextToken(json, ref index);
bool done = false;
while (!done) {
token = LookAhead(json, index);
if (token == JSON.TOKEN_NONE) {
success = false;
return null;
} else if (token == JSON.TOKEN_COMMA) {
NextToken(json, ref index);
} else if (token == JSON.TOKEN_CURLY_CLOSE) {
NextToken(json, ref index);
return table;
} else {
// name
string name = ParseString(json, ref index, ref success);
if (!success) {
success = false;
return null;
}
// :
token = NextToken(json, ref index);
if (token != JSON.TOKEN_COLON) {
success = false;
return null;
}
// value
object value = ParseValue(json, ref index, ref success);
if (!success) {
success = false;
return null;
}
table[name] = value;
}
}
return table;
}
protected static ArrayList ParseArray(char[] json, ref int index, ref bool success)
{
ArrayList array = new ArrayList();
// [
NextToken(json, ref index);
bool done = false;
while (!done) {
int token = LookAhead(json, index);
if (token == JSON.TOKEN_NONE) {
success = false;
return null;
} else if (token == JSON.TOKEN_COMMA) {
NextToken(json, ref index);
} else if (token == JSON.TOKEN_SQUARED_CLOSE) {
NextToken(json, ref index);
break;
} else {
object value = ParseValue(json, ref index, ref success);
if (!success) {
return null;
}
array.Add(value);
}
}
return array;
}
protected static object ParseValue(char[] json, ref int index, ref bool success)
{
switch (LookAhead(json, index)) {
case JSON.TOKEN_STRING:
return ParseString(json, ref index, ref success);
case JSON.TOKEN_NUMBER:
return ParseNumber(json, ref index, ref success);
case JSON.TOKEN_CURLY_OPEN:
return ParseObject(json, ref index, ref success);
case JSON.TOKEN_SQUARED_OPEN:
return ParseArray(json, ref index, ref success);
case JSON.TOKEN_TRUE:
NextToken(json, ref index);
return true;
case JSON.TOKEN_FALSE:
NextToken(json, ref index);
return false;
case JSON.TOKEN_NULL:
NextToken(json, ref index);
return null;
case JSON.TOKEN_NONE:
break;
}
success = false;
return null;
}
protected static string ParseString(char[] json, ref int index, ref bool success)
{
StringBuilder s = new StringBuilder(BUILDER_CAPACITY);
char c;
EatWhitespace(json, ref index);
// "
c = json[index++];
bool complete = false;
while (!complete) {
if (index == json.Length) {
break;
}
c = json[index++];
if (c == '"') {
complete = true;
break;
} else if (c == '\\') {
if (index == json.Length) {
break;
}
c = json[index++];
if (c == '"') {
s.Append('"');
} else if (c == '\\') {
s.Append('\\');
} else if (c == '/') {
s.Append('/');
} else if (c == 'b') {
s.Append('\b');
} else if (c == 'f') {
s.Append('\f');
} else if (c == 'n') {
s.Append('\n');
} else if (c == 'r') {
s.Append('\r');
} else if (c == 't') {
s.Append('\t');
} else if (c == 'u') {
int remainingLength = json.Length - index;
if (remainingLength >= 4) {
// parse the 32 bit hex into an integer codepoint
uint codePoint;
if (!(success = UInt32.TryParse(new string(json, index, 4), NumberStyles.HexNumber, CultureInfo.InvariantCulture, out codePoint))) {
return "";
}
// convert the integer codepoint to a unicode char and add to string
s.Append(Char.ConvertFromUtf32((int)codePoint));
// skip 4 chars
index += 4;
} else {
break;
}
}
} else {
s.Append(c);
}
}
if (!complete) {
success = false;
return null;
}
return s.ToString();
}
protected static double ParseNumber(char[] json, ref int index, ref bool success)
{
EatWhitespace(json, ref index);
int lastIndex = GetLastIndexOfNumber(json, index);
int charLength = (lastIndex - index) + 1;
double number;
success = Double.TryParse(new string(json, index, charLength), NumberStyles.Any, CultureInfo.InvariantCulture, out number);
index = lastIndex + 1;
return number;
}
protected static int GetLastIndexOfNumber(char[] json, int index)
{
int lastIndex;
for (lastIndex = index; lastIndex < json.Length; lastIndex++) {
if ("0123456789+-.eE".IndexOf(json[lastIndex]) == -1) {
break;
}
}
return lastIndex - 1;
}
protected static void EatWhitespace(char[] json, ref int index)
{
for (; index < json.Length; index++) {
if (" \t\n\r".IndexOf(json[index]) == -1) {
break;
}
}
}
protected static int LookAhead(char[] json, int index)
{
int saveIndex = index;
return NextToken(json, ref saveIndex);
}
protected static int NextToken(char[] json, ref int index)
{
EatWhitespace(json, ref index);
if (index == json.Length) {
return JSON.TOKEN_NONE;
}
char c = json[index];
index++;
switch (c) {
case '{':
return JSON.TOKEN_CURLY_OPEN;
case '}':
return JSON.TOKEN_CURLY_CLOSE;
case '[':
return JSON.TOKEN_SQUARED_OPEN;
case ']':
return JSON.TOKEN_SQUARED_CLOSE;
case ',':
return JSON.TOKEN_COMMA;
case '"':
return JSON.TOKEN_STRING;
case '0': case '1': case '2': case '3': case '4':
case '5': case '6': case '7': case '8': case '9':
case '-':
return JSON.TOKEN_NUMBER;
case ':':
return JSON.TOKEN_COLON;
}
index--;
int remainingLength = json.Length - index;
// false
if (remainingLength >= 5) {
if (json[index] == 'f' &&
json[index + 1] == 'a' &&
json[index + 2] == 'l' &&
json[index + 3] == 's' &&
json[index + 4] == 'e') {
index += 5;
return JSON.TOKEN_FALSE;
}
}
// true
if (remainingLength >= 4) {
if (json[index] == 't' &&
json[index + 1] == 'r' &&
json[index + 2] == 'u' &&
json[index + 3] == 'e') {
index += 4;
return JSON.TOKEN_TRUE;
}
}
// null
if (remainingLength >= 4) {
if (json[index] == 'n' &&
json[index + 1] == 'u' &&
json[index + 2] == 'l' &&
json[index + 3] == 'l') {
index += 4;
return JSON.TOKEN_NULL;
}
}
return JSON.TOKEN_NONE;
}
protected static bool SerializeValue(object value, StringBuilder builder)
{
bool success = true;
if (value is string) {
success = SerializeString((string)value, builder);
} else if (value is Hashtable) {
success = SerializeObject((Hashtable)value, builder);
} else if (value is ArrayList) {
success = SerializeArray((ArrayList)value, builder);
} else if ((value is Boolean) && ((Boolean)value == true)) {
builder.Append("true");
} else if ((value is Boolean) && ((Boolean)value == false)) {
builder.Append("false");
} else if (value is ValueType) {
// thanks to ritchie for pointing out ValueType to me
success = SerializeNumber(Convert.ToDouble(value), builder);
} else if (value == null) {
builder.Append("null");
} else {
success = false;
}
return success;
}
protected static bool SerializeObject(Hashtable anObject, StringBuilder builder)
{
builder.Append("{");
IDictionaryEnumerator e = anObject.GetEnumerator();
bool first = true;
while (e.MoveNext()) {
string key = e.Key.ToString();
object value = e.Value;
if (!first) {
builder.Append(", ");
}
SerializeString(key, builder);
builder.Append(":");
if (!SerializeValue(value, builder)) {
return false;
}
first = false;
}
builder.Append("}");
return true;
}
protected static bool SerializeArray(ArrayList anArray, StringBuilder builder)
{
builder.Append("[");
bool first = true;
for (int i = 0; i < anArray.Count; i++) {
object value = anArray[i];
if (!first) {
builder.Append(", ");
}
if (!SerializeValue(value, builder)) {
return false;
}
first = false;
}
builder.Append("]");
return true;
}
protected static bool SerializeString(string aString, StringBuilder builder)
{
builder.Append("\"");
char[] charArray = aString.ToCharArray();
for (int i = 0; i < charArray.Length; i++) {
char c = charArray[i];
if (c == '"') {
builder.Append("\\\"");
} else if (c == '\\') {
builder.Append("\\\\");
} else if (c == '\b') {
builder.Append("\\b");
} else if (c == '\f') {
builder.Append("\\f");
} else if (c == '\n') {
builder.Append("\\n");
} else if (c == '\r') {
builder.Append("\\r");
} else if (c == '\t') {
builder.Append("\\t");
} else {
int codepoint = Convert.ToInt32(c);
if ((codepoint >= 32) && (codepoint <= 126)) {
builder.Append(c);
} else {
builder.Append("\\u" + Convert.ToString(codepoint, 16).PadLeft(4, '0'));
}
}
}
builder.Append("\"");
return true;
}
protected static bool SerializeNumber(double number, StringBuilder builder)
{
builder.Append(Convert.ToString(number, CultureInfo.InvariantCulture));
return true;
}
}
//parse and show entire json in key-value pair
Hashtable HTList = (Hashtable)JSON.JsonDecode("completejsonstring");
public void GetData(Hashtable HT)
{
IDictionaryEnumerator ienum = HT.GetEnumerator();
while (ienum.MoveNext())
{
if (ienum.Value is ArrayList)
{
ArrayList arnew = (ArrayList)ienum.Value;
foreach (object obj in arnew)
{
Hashtable hstemp = (Hashtable)obj;
GetData(hstemp);
}
}
else
{
Console.WriteLine(ienum.Key + "=" + ienum.Value);
}
}
}

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