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Pick only one record from a JSON array in C#

I'm trying to extract a record from a JSON array but it doesn't seem to work.
Here my code :
DataTable table = ConvertJsonToDatatable(responseBody);
System.Windows.Forms.MessageBox.Show(table.Columns[1].ToString(), "transformation");
The MessageBox isn't showing. I have checked responseBody and the variable isn't empty at all.
Here the structure of this variable (and the JSON array rear)
{
"data":
[
[
1651217520000,
1.0562,
1.0562,
1.056,
1.0561,
0,
0
],
[
1651217580000,
1.0561,
1.0563,
1.0561,
1.0561,
0,
0
]
],
"events": null
}
public static DataTable ConvertJsonToDatatable(string jsonString)
{
var jsonLinq = JObject.Parse(jsonString);
// Find the first array using Linq
var linqArray = jsonLinq.Descendants().Where(x => x is JArray).First();
var jsonArray = new JArray();
foreach (JObject row in linqArray.Children<JObject>())
{
var createRow = new JObject();
foreach (JProperty column in row.Properties())
{
// Only include JValue types
if (column.Value is JValue)
{
createRow.Add(column.Name, column.Value);
}
}
jsonArray.Add(createRow);
}
return JsonConvert.DeserializeObject<DataTable>(jsonArray.ToString());
}
Does anyone have an idea of how to extract/pick one value from this array (which is a string in my code) ?
Have a nice week end everyone and thanks in advance

you have to fix table creating code
public static DataTable ConvertJsonToDatatable(string jsonString)
{
var jsonLinq = JObject.Parse(jsonString);
// Find the first array using Linq
var linqArray = jsonLinq.Descendants().Where(x => x is JArray).First();
//or maybe this would be enough
var linqArray = JObject.Parse(jsonString)["data"];
var jsonArray = new JArray();
foreach (var row in (JArray)linqArray)
{
var createdRow = new JObject();
var i = 0;
foreach (var item in row)
{
i++;
createdRow.Add("col" + i.ToString(), (string)item);
}
jsonArray.Add(createdRow);
}
return jsonArray.ToObject<DataTable>();
}
how to use
DataTable table = ConvertJsonToDatatable(responseBody);
string val = table.Rows[0].Field<string>("col2");
System.Windows.Forms.MessageBox.Show(val, "transformation");

i probably would be marked negative, but i try to explain how it looks like inside. i made example to show tow to get back list of arrays it might visualize for you.
void Main()
{
string json = "{\"data\":[[1651217520000,1.0562,1.0562,1.056,1.0561,0,0],[1651217580000,1.0561,1.0563,1.0561,1.0561,0,0]],\"events\":null}";
var obj = JObject.Parse(json);
foreach (JToken token in obj.FindTokens("data"))
{
foreach (JArray row in JArray.Parse(token.ToString()))
{
row.Dump();
row[0].Dump("first element");
}
}
}
public static class JsonExtensions
{
public static List<JToken> FindTokens(this JToken containerToken, string name)
{
List<JToken> matches = new List<JToken>();
FindTokens(containerToken, name, matches);
return matches;
}
private static void FindTokens(JToken containerToken, string name, List<JToken> matches)
{
if (containerToken.Type == JTokenType.Object)
{
foreach (JProperty child in containerToken.Children<JProperty>())
{
if (child.Name == name)
{
matches.Add(child.Value);
}
FindTokens(child.Value, name, matches);
}
}
else if (containerToken.Type == JTokenType.Array)
{
foreach (JToken child in containerToken.Children())
{
FindTokens(child, name, matches);
}
}
}
}
result would be an array of jarray
so you can build you DataTable rows

.Dump() is a left over from linqpad. Good tool. Same as console.write

How to access properties of the object type c#?

var obj1 = new A()
{
Name = "abc",
Id = 1
}
var obj2 = new B()
{
Place = "XYZ",
Pincode = 123456
}
var obj3 = new C()
{
Mark = 100,
Standard = "Tenth"
}
var myList = new List<object>();
myList .add(obj1);
myList .add(obj2);
myList .add(obj3);
This is my code structure. I need to access the properties of the myList object. i.e) I need to access the properties like Name, Id, Place, Pincode, Mark, Standard from the myList object and it's corresponding values.
How to achieve it?

As I wrote in my comment, usually keeping completely different types in the same collection is wrong. However, that doesn't mean that's always the case, and so assuming you have a good enough reason to do that - here's one option to do it.
Assuming c# 7 or higher, your best option would probably be to (ab)use switch with pattern matching:
foreach(var obj in myList)
{
switch(obj)
{
case A a:
DoSomethingWithA(a);
break;
case B b:
DoSomethingWithB(b);
break;
}
}

You can try something like below. Working code here
public static List<List<string>> GetProperties(List<object> myList)
{
// If you don't want two lists, you can use Dictionary<key, value>
List<string> props = new List<string>();
List<string> values = new List<string>();
foreach (var a in myList)
{
if(a == null)
continue;
var propsInfo = a.GetType().GetProperties();
foreach (var prop in propsInfo)
{
if(!props.Contains(prop.Name))
{
props.Add(prop.Name);
values.Add(prop.GetValue(a, null).ToString());
}
}
}
return new List<List<string>> { props, values};
}

If you are simply looking to get values out of an object (property values), that is a different story.
foreach (objectType obj in mylist)
{
someVariable1 = obj.name;
someVariable2 = obj.Id;
}

Here is some code I use to compare two objects. I don't know if this is your scenario but I hope it helps you get what you need it for.
protected List<string> GetProperties(List<object> myList)
{
List<string> props = new List<string>();
foreach (var a in myList)
{
if(a == null)
continue;
var propsInfo = a.GetType().GetProperties();
foreach (var prop in propsInfo)
{
if(!props.Contains(prop.Name))
{
props.Add(prop.Name);
}
}
}
return props;
}

IDictionary<String, List<OpenXmlCompositeElement>> - get the List<OpenXmlCompositeElement>?

I'm working with Open XML & I have a IDictionary<String, List<OpenXmlCompositeElement>> structure. I want to work with the List part of the structure but this.map.Values tries to wrap it in an ICollection. How can I get the List part from my structure?
public List<OpenXmlCompositeElement> MapData()
{
//this does not work
return this.map.Values;
}

Since it is a dictionary, it expects you to tell from which key you want the value.
So this would be the code you need, where yourKey is the key you want to retrieve:
public List<OpenXmlCompositeElement> MapData()
{
return this.map["yourKey"];
}
If you have no interest in the key, and the dictionary is just a dictionary because the serializer says so, you could get the first item for example like this:
public List<OpenXmlCompositeElement> MapData()
{
return this.map.Values.First();
}

You can either loop through the dictionary and use the value you would like, or access the List directly using the key (in this case it's a string)
IDictionary<String, List<OpenXmlCompositeElement>> myDictionary;
List<OpenXmlCompositeElement> myList = myDictionary["myKey"];
Where myKey is available in the dictionary.
Alternatively you can loop through
foreach (var item in myDictionary)
{
var key = item.Key;
var value = item.Value
// You could then use `key` if you are unsure of what
// items are in the dictionary
}

Assuming this is your dictionary...
IDictionary<string, List<OpenXmlCompositeElement>> items = ...;
Get a specific List by key...
List<OpenXmlCompositeElement> list = items["key"];
Get the first list in the dictionary...
List<OpenXmlCompositeElement> list = items.Values.First();
Concatenate all lists in the dictionary into a single list...
List<OpenXmlCompositeElement> list = items.SelectMany(o => o).ToList();

foreach(KeyValuePair<string, List<OpenXmlCompositeElement>> kvp in IDictionary)
{
string key = kvp.key
List<OpenXmlCompositeElement> list = kvp.Value;
foreach(OpenXmlCompositeElement o in list)
{
Do anything you need to your List here
}
}
I am working with dictionaries as well, so here is a real example that I am currently working with:
foreach(KeyValuePair<string, List<DataRecords>> kvp in vSummaryResults)
{
string sKey = kvp.Key;
List<DataRecords> list = kvp.Value;
string[] vArr = sKey.Split(',');
int iTotalTradedQuant = 0;
double dAvgPrice = 0;
double dSumQuantPrice = 0;
double dQuantPrice = 0;
double dNumClose = 0;
foreach (DataRecords rec in list)
{
if(vSummaryResults.ContainsKey(sKey))
{
iTotalTradedQuant += rec.iQuantity;
dQuantPrice = rec.iQuantity * rec.dInputTradePrice;
dSumQuantPrice += dQuantPrice;
dAvgPrice = dSumQuantPrice / iTotalTradedQuant;
dNumClose = rec.dNumericClosingPrice;
}
else
{
vSummaryResults.Add(sKey, list);
//dNumClose = rec.dNumericClosingPrice;
}

How to compare key/value dictionary with == operator on a IReadOnlyCollection<string>?

I have a MultiValueDictionary<string, string> where I am trying to get a key by value.
var dic = na.prevNext; // Getter to get MultiValueDictionary
string nodePointingToThisOne = "";
foreach (var item in dic)
{
if(item.Value == "test")
{
nodePointingToThisOne = item.Key;
}
break;
}
This does not work so I tried Linq:
string nodePointingToThisOne = dic.Where(x => x.Value == this.nodeID).Select(x => x.Key);
But on both I get this error: Operator '==' cannot be applied to operands of type 'System.Collections.Generic.IReadOnlyCollection<string>' and 'string'
So my question is how do I make this comparison work for a read-only collection? I am aware that I get problems if a key exists multiple times but I reduced the problem to this one for now.
I read
Get Dictionary key by using the dictionary value
LINQ: Getting Keys for a given list of Values from Dictionary and vice versa
get dictionary key by value
Getting key of value of a generic Dictionary?
Get key from value - Dictionary<string, List<string>>
but they deal with a "normal" dictionary.

Since the Value property it self may contain multiple values you can't compare it directly against certain string using == operator. Use Contains() instead :
.....
if (item.Value.Contains("test"))
{
.....
}
...or in method chain version :
string nodePointingToThisOne = dic.Where(x => x.Value.Contains("test"))
.Select(x => x.Key)
.FirstOrDefault();

Try to iterate by Keys and then compare the value, and return the Key only if the Value matches.
Like this:
foreach (var key in dic.Keys)
{
if(dic[key].Contains("your value"))
return key;
}

You can iterate over keys like this
foreach (var key in dic.Keys)
{
if(key == "your key")
return key;
}
You can also iterate over values like this
foreach (var v in dic.Values)
{
if(v == "your value")
return v;
}
Example:
Dictionary<string, string> c = new Dictionary<string, string>();
c.Add("Pk", "Pakistan");
c.Add("Aus", "Australia");
c.Add("Ind", "India");
c.Add("Nz", "New Zeland");
c.Add("SA", "South Africa");
foreach (var v in c.Values)
{
if (v == "Australia")
{
Console.WriteLine("Your Value is = " + v);
// perform your task
}
}
foreach (var k in c.Keys)
{
if (k == "Aus")
{
// perform your task
Console.WriteLine("Your Key is = " + k);
}
}
Output:
Your Value is = "Australia"
Your Key is = "Aus"

If you look at the MultiValueDictionary, line 81 will give you a hint. It is:
[TestInitialize]
public void TestInitialize()
{
MultiValueDictionary = new MultiValueDictionary<TestKey, string>();
}
protected static void AssertAreEqual( IDictionary<TestKey, string[]> expected,
IMultiValueDictionary<TestKey, string> actual )
{
Assert.AreEqual( expected.Count, actual.Count );
foreach ( var k in expected.Keys )
{
var expectedValues = expected[ k ];
var actualValues = actual[ k ];
AssertAreEqual( expectedValues, actualValues );
}
}
So for your case, the solution is similar:
foreach (var item in dic.keys)
{
if(dict[item] == "test")
{
nodePointingToThisOne = item;
return nodePointingToThisOne;
}
}

worked for me:
foreach (int i in Dictionary.Keys)
{
if (Dictionary.Values.ToString() == "Your Value")
{
return Dictionary.Keys;
}
}

Identifying that a property's value is an array

I have a JSON file:
{
"abn":"63119059513",
"acn":"119059513",
"business_structure":"Private Company",
"ngr_number":"1231231",
"cbh_number":"1231231",
"main_name":"Brickworks Building Products Pty Ltd",
"trading_name":"Brickworks",
"other_trading_names":"Austral Bricks",
"directors":[
{
"ID":"12114",
"ae_forms_filled_in_ID":"22739",
"name":"John Smith",
"dob":"1983-10-29",
"address_line_1":"123 Fake Street",
"address_line_2":"",
"address_line_city":"Fakeland",
"address_line_postcode":"2000",
"address_line_state":"New South Wales",
"address_line_country":"Australia",
"order_extract_id":null,
"director_found":null,
"drivers_lic":"",
"home_mortgage":"",
"phone":"",
"mobile":"",
"director_email":"",
"director_title":"Mr",
"director_position":"Director",
"dir_pdf_url":null
}
],
}
I want to determine if the value of any property has a structure of an array. The best I can come up with so far is:
StreamReader streamrr = new StreamReader("C:\\temp\\agfarm_example_udate.json", Encoding.UTF8);
string JSON = streamrr.ReadToEnd();
JObject CWFile = JObject.Parse(JSON);
foreach (JProperty property in CWFile.Properties())
{
// Do something
if (property.Value.ToString().Contains("["))
{
// Do something with the array
JArray items = (JArray)CWFile[property.Name];
foreach (JObject o in items.Children<JObject>())
{
foreach (JProperty p in o.Properties())
{
// Do something
}
}
}
}
To determine whether or not a property value has an array, I used the condition:
if (property.Value.ToString().Contains("["))
I'm just wondering if there is a better way of doing this check?

One way to do this is to check the JToken.Type property. Arrays are of type JTokenType.Array:
if (property.Value.Type == JTokenType.Array)
{
var items = (JArray)property.Value;
// Proceed as before.
}
Or, you can just try to cast to JArray:
if (property.Value is JArray)
{
var items = (JArray)property.Value;
// Proceed as before.
}
Both are preferable to checking property.Value.ToString().Contains("[") since a nested property might have an array value, thus causing a bracket to appear somewhere in the ToString() return.
If you want to recursively find every property with an array value, you can introduce an extension method:
public static class JsonExtensions
{
public static IEnumerable<JToken> WalkTokens(this JToken node)
{
if (node == null)
yield break;
yield return node;
foreach (var child in node.Children())
foreach (var childNode in child.WalkTokens())
yield return childNode;
}
}
And then do:
var CWFile = JToken.Parse(JSON)
var arrayProperties = CWFile.WalkTokens().OfType<JProperty>().Where(prop => prop.Value.Type == JTokenType.Array);

public void Traverse(string name, JToken j)
{
foreach (JToken token in j.AsJEnumerable())
if (token.Type == JTokenType.Object)
{
foreach (var pair in token as JObject)
{
string name_ = pair.Key;
JToken child = pair.Value;
Traverse(name, child);
}
}
else if (token.Type == JTokenType.Array) //an array property found
{
foreach (var child in token.Children())
Traverse(((JProperty)j).Name, child);
}
else if (token.Type == JTokenType.Property)
{
var property = token as JProperty; //current level property
Traverse(name, (JContainer)token);
}
else //current level property name & value
{
var nm = "";
var t = "";
if (j is JProperty)
{
nm = ((JProperty)j).Name;
t = Convert.ToString(((JProperty)j).Value);
}
t = Convert.ToString(token);
}
}
Call:
JSON = JObject.Parse(...);
Traverse("", JSON);
To parse and already parsed text for the same reason is not very wise :
if (property.Value.ToString().Contains("["))
Json structure is simple : objects, arrays, properties, values
http://www.json.org/
So array is a wellknown object for json and we are looking for it :
if (token.Type == JTokenType.Array) //an array property