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Find specific part of string based on condition

I have below comma separated string. This string contains relation which is needed in the application for processing.
string userInputColRela = "input1:Student_Name, input2:Student_Age";
Now, i need to extract Student_Name if i provide input as input1 and Student_Age if the input provided is input2.
How can i achieve this? I know i can go with looping but that will be a little lengthy solution, what is other way round?

You could parse the input string by splitting firstly on the comma, then again on the semi-colon to get the key-value pairs contained in it in dictionary form. For example:
string userInputColRela = "input1: Student_Name, input2: Student_Age";
var inputLookup = userInputColRela
.Split(',')
.Select(a => a.Split(':'))
.ToDictionary(a => a[0].Trim(), a => a[1].Trim());
var studentName = inputLookup["input1"];

If your strings are always in the format input1:Student_Name, input2:Student_Age then probably you can use a Dictionary<k,v> and Split() function like
string userInputColRela = "input1:Student_Name, input2:Student_Age";
string input = "input1";
var args = userInputColRela.Split(',');
Dictionary<string, string> inputs = new Dictionary<string, string>();
foreach (var item in args)
{
var data = item.Split(':');
inputs.Add(data[0], data[1]);
}
Console.WriteLine(inputs[input]);

How can I Read Dynamic String and Store each key string Value into a varaible?

This is my dynamic String:
String a= "SourceFilePath:C:\Users\Anuj\Desktop\Anuj Tamrakar Working Folder, BackUpFilePath:C:\Users\Anuj\Desktop\installer, SyncPath:C:\Users\Anuj\Desktop\PSI, Password:3SMpUGoJpIJdWwRDXau+OQ==, NumberOfTimes:2, Time0:10:10 AM, Time1:10:10 PM"
I need to read the contents of the string and need to store each key and its coressponding values into variable. I need Output like
var SourceFilePath = "C:\Users\Anuj\Desktop\Anuj Tamrakar Working Folder";
var BackUpFilePath="C:\Users\Anuj\Desktop\installer"
var SyncPath="C:\Users\Anuj\Desktop\PSI"
var Password="3SMpUGoJpIJdWwRDXau+OQ=="
var NumberOfTimes=2
var Time0=10:10 AM
var Time1=10:10 PM
This Part is Dynamic one:
var NumberOfTimes:2
var Time0:10:10 AM
var Time1:10:10 PM
If I have NumberOfTimes:4 on my String File. I would Have 4 Time values i.e. Time0,Time1,Time2 and Time3. So i need to store these 4 time values into 4 variables

I tried this in a console app and works fine. Below is my solution.
static void Main(string[] args)
{
String a = #"SourceFilePath:C:\Users\Anuj\Desktop\Anuj Tamrakar Working Folder, BackUpFilePath:C:\Users\Anuj\Desktop\installer, SyncPath:C:\Users\Anuj\Desktop\PSI, Password:3SMpUGoJpIJdWwRDXau+OQ==, NumberOfTimes:2, Time0:10:10 AM, Time1:10:10 PM";
Dictionary<string, string> processedString = ProcessString(a);
//Here you can set the values to variable accessing it from the Dictionary
var SourceFilePath = processedString["SourceFilePath"];
var BackUpFilePath = processedString["BackUpFilePath"];
var SyncPath = processedString["SyncPath"];
var Password = processedString["Password"];
var NumberOfTimes = Convert.ToInt32(processedString["NumberOfTimes"]);
// And for the dynamic variables like Time01, Time02 I recommend you to create a list which holds all the time components.
// Because creating a variable on the fly will be more complex for your requirement and is not necessary at this moment.
//So you can do this
var TimeComponents = processedString.Where(x => x.Key.StartsWith("Time")).Select(x => x).ToList();
Console.ReadLine();
}
And the process of splitting up the string and creating a dictionary is as below.
public static Dictionary<string, string> ProcessString(string toProcess)
{
Dictionary<string, string> processedString = new Dictionary<string, string>();
var eachSubString = toProcess.Split(',');
foreach (var subStr in eachSubString)
{
var keyValue = subStr.Trim().Split(new char[] { ':' }, 2);
processedString.Add(keyValue[0], keyValue[1]);
}
return processedString;
}
And here is the screen shot of the debugger
Let me know if this helps.

You could use a dictionary object.
Split string input on , then loop through variable key value pairs splitting on :.
Store key and value in dictionary.
You don't need to declare each variable but you could look it up in the dictionary by the key.

It must be something like below.
// you can also fill an array dynamically
var NumberOfTimes=["10:10 AM","10:11 AM","10:12 AM"]
//count of stored items in array
NumberOfTimes.length
//in order to print or use in some where else
NumberOfTimes.forEach(function(e,i){
//do somethings
});

How to do a multiple case insensitive replace using a StringBuilder

I have a (large) template and want to replace multiple values. The replacement needs to be done case insensitive. It must also be possible to have keys that does not exist in the template.
For example:
[TestMethod]
public void ReplaceMultipleWithIgnoreCaseText()
{
const string template = "My name is #Name# and I like to read about #SUBJECT# on #website#, tag #subject#";
const string expected = "My name is Alex and I like to read about C# on stackoverflow.com, tag C#";
var replaceParameters = new List<KeyValuePair<string, string>>
{
new KeyValuePair<string, string>("#name#","Alex"),
new KeyValuePair<string, string>("#subject#","C#"),
new KeyValuePair<string, string>("#website#","stackoverflow.com"),
// Note: The next key does not exist in template
new KeyValuePair<string, string>("#country#","The Netherlands"),
};
var actual = ReplaceMultiple(template, replaceParameters);
Assert.AreEqual(expected, actual);
}
public string ReplaceMultiple(
string template,
IEnumerable<KeyValuePair<string, string>> replaceParameters)
{
throw new NotImplementedException(
"Implementation needed for many parameters and long text.");
}
Note that if I have a list of 30 parameters and a large template, I do not want 30 large strings in memory. Using a StringBuilder seems to be an option, but other solutions are also welcome.
Solution I tried but did not work
Solution found here (C# String replace with dictionary) throws an exception when a key is not in the colletion, but our users makes mistakes and in that case I want to just leave the wromg key in the text. Example:
static readonly Regex re = new Regex(#"\$(\w+)\$", RegexOptions.Compiled);
static void Main2()
{
// "Name" is accidentally typed by a user as "nam".
string input = #"Dear $nam$, as of $date$ your balance is $amount$";
var args = new Dictionary<string, string>(
StringComparer.OrdinalIgnoreCase) {
{"name", "Mr Smith"},
{"date", "05 Aug 2009"},
{"amount", "GBP200"}};
// Works, but not case insensitive and
// uses a lot of memory when using a large template
// ReplaceWithDictionary many args
string output1 = input;
foreach (var arg in args)
{
output1 = output1.Replace("$" + arg.Key +"$", arg.Value);
}
// Throws a KeyNotFoundException + Only works when data is tokenized
string output2 = re.Replace(input, match => args[match.Groups[1].Value]);
}

Using a StringBuilder seems to be an option, but other solutions are also welcome.
Since you want case insensitive, I'd suggest (non StringBuilder):
public static string ReplaceMultiple(
string template,
IEnumerable<KeyValuePair<string, string>> replaceParameters)
{
var result = template;
foreach(var replace in replaceParameters)
{
var templateSplit = Regex.Split(result,
replace.Key,
RegexOptions.IgnoreCase);
result = string.Join(replace.Value, templateSplit);
}
return result;
}
DotNetFiddle Example

This is based off of Marc's answer the only real change is the check during the replacement and the boundary regex rule:
static readonly Regex re = new Regex(#"\b(\w+)\b", RegexOptions.Compiled);
static void Main(string[] args)
{
string input = #"Dear Name, as of dAte your balance is amounT!";
var replacements = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase)
{
{"name", "Mr Smith"},
{"date", "05 Aug 2009"},
{"amount", "GBP200"}
};
string output = re.Replace(input, match => replacements.ContainsKey(match.Groups[1].Value) ? replacements[match.Groups[1].Value] : match.Groups[1].Value);
}
And here is a 5000 iterations test benchmark, have not looked at memory or anything else.
Replacement function is the one you have checked as the accepted answer.

I think I might have something you could try. I used something similar to it for email templates
public string replace()
{
string appPath = Request.PhysicalApplicationPath;
StreamReader sr = new StreamReader(appPath + "EmailTemplates/NewMember.txt");
string template = sr.ReadToEnd();
template = template.Replace("<%Client_Name%>",
first_name.Text + " " + middle_initial.Text + " " + last_name.Text);
//Add Customer data
template = template.Replace("<%Client_First_Name%>", first_name.Text);
template = template.Replace("<%Client_MI%>", middle_initial.Text);
template = template.Replace("<%Client_Last_Name%>", last_name.Text);
template = template.Replace("<%Client_DOB%>", dob.Text);
return template;
}
Inside of your template you can have tags such as <% %> as place holders for the values you want
Hope this helps!

The answer of Marc Gravell: C# String replace with dictionary can be changed an little bit so it does not throws an exception when the match can not be found. In this case it simply does not replace the match.
In case the string to be replace is tokenized, this is the solution:
static readonly Regex RegExInstance = new Regex(#"\$(\w+)\$", RegexOptions.Compiled);
public string ReplaceWithRegEx(string template, Dictionary<string, string> parameters)
{
return RegExInstance.Replace(template, match => GetNewValue(parameters, match));
}
private string GetNewValue(Dictionary<string, string> parameters, Match match)
{
var oldValue = match.Groups[1].Value;
string newValue;
var found = parameters.TryGetValue(oldValue, out newValue);
if (found)
{
return newValue;
}
var originalValue = match.Groups[0].Value;
return originalValue;
}
I have tested the solution with a 100.000 bytes string, 7 keys and hundreds of replacements. It uses 7 times more memory then the lenght of the string. And it took only 0.002 seconds.

c# - regex to find a string that comes after = [duplicate]

This question already has answers here:
regex to find a string that comes after =
(6 answers)
Closed 9 years ago.
So I asked this question before and said I wanted it in javascript but realized later on that it's unecessary data being sent. So it would be great if anybody could help me solve the same thing in C#
What I need is to get several properties out of a string.
The string will look something like:
str = "car[brand=saab][wheels=4]";
There can be more or fewer properties.
I need everything before the first [] in 1 variable.
Then I need each property and its value in a variable.
Easiest way to understand what I want is probably to check my previous question and the answer that solved it :)

I used the regex(slightly different) in your previous question.
string input = "car[brand=saab][wheels=4]";
string product = "";
Dictionary<string, string> props = new Dictionary<string, string>();
foreach (Match m in Regex.Matches(input, #"^(\w+)|\[(\w+)=(.+?)\]"))
{
if (String.IsNullOrEmpty(product))
product = m.Groups[1].Value;
else
props.Add(m.Groups[2].Value, m.Groups[3].Value);
}

try this regex:
(.+?)(\[.+?\])+
and a sample code:
var inputString = "car[brand=saab][wheels=4]";
var pattern = #"(?<v1>.+?)(?<v2>\[.+?\])+";
var v1 = Regex.Match(inputString, pattern).Groups["v1"].Value;
Dictionary<String, String> list = new Dictionary<String, String>();
foreach (Capture capture in Regex.Match(inputString, pattern).Groups["v2"].Captures)
{
var sp = capture.Value.Split('=');
list.Add(sp[0], sp[1]);
}
explain:
(?<name>subexpression)
Captures the matched subexpression into a named group.

You can do this
var lst=Regex.Matches(input,#"(\w+)((?:\[.*?\])+)")
.Cast<Match>()
.Select(x=>new
{
name=x.Groups[1].Value,
value=Regex.Matches(x.Groups[2].Value,#"(?<=\[).*?(?=\])")
.Cast<Match>()
.Select(x=>new
{
name=x.Groups[0].Value.Split('=')[0],
value=x.Groups[0].Value.Split('=')[1]
})
});
Now you can iterate over lst like this
foreach(var parent in lst)
{
parent.name;//car
foreach(var pairs in parent.value)
{
pairs.name;//brand,wheels
pairs.value;//ferrari,4
}
}
So,for input car[brand=a][wheels=4]cycle[brand=b][wheels=2]
Output would be like
car
brand,a
wheels,4
cycle
brand,b
wheels,2

Without regex:
string input = "car[brand=saab][wheels=4]";
var query = from s in input.Replace("]", "").Split('[')
let vars = s.Split('=')
let name = vars[0]
let value = vars.Length > 1 ? vars[1] : ""
select new {Name = name, Value = value};
string firstVar = query.First().Name;
Dictionary<string, string> otherVars = query
.Skip(1)
.ToDictionary(v => v.Name, v => v.Value);
You can access your variables in the dictionary like this string brand = otherVars["brand"]

Since you already have an answer using regex and your comments state it doesn't have to be with a regex, I'll offer an alternative:
The code is
string str = ("car[brand=saab][wheels=4]");
int i = str.IndexOf("[");
string[] details =str.Substring(i).Replace("]","").Split('[');
string name = str.Substring(0, i);
string brand = details[1].Split('=')[1];
string wheels = details[2].Split('=')[1];
This approach assumes the data is always going to be in the same format though; you may need some validation in there depending on your needs...

How can you change a ";" seperated string to some kind of dictionary?

I have a string like this:
"user=u123;name=Test;lastname=User"
I want to get a dictionary for this string like this:
user "u123"
name "Test"
lastname "User"
this way I can easely access the data within the string.
I want to do this in C#.
EDIT:
This is what I have so far:
public static Dictionary<string, string> ValueToDictionary(string value)
{
Dictionary<string, string> result = null;
result = new Dictionary<string, string>();
string[] values = value.Split(';');
foreach (string val in values)
{
string[] valueParts = val.Split('=');
result.Add(valueParts[0], valueParts[1]);
}
return result;
}
But to be honest I really think there is a better way to do this.
Cheers,
M.

You can use LINQ:
var text = "user=u123;name=Test;lastname=User";
var dictionary = (from t in text.Split( ";".ToCharArray() )
let pair = t.Split( "=".ToCharArray(), 2 )
select pair).ToDictionary( p => p[0], p => p[1] );

Split the string by ";".
Iterate over every element in the resulting array and split every element by "=".
Now;
dictionary.add(element[0], element[1]);
I Hope I made it clear enough.

Dictionary<string, string> d = new Dictionary<string, string>();
string s1 = "user=u123;name=Test;lastname=User";
foreach (string s2 in s1.Split(';'))
{
string[] split = s2.Split('=');
d.Add(split[0], split[1]);
}

var dictionary = new Dictionary<string, string>();
var linedValue = "user=u123;name=Test;lastname=User";
var kvps = linedValue.Split(new[] { ';' }); // you may use StringSplitOptions.RemoveEmptyEntries
foreach (var kvp in kvps)
{
var kvpSplit = kvp.Split(new[] { '=' });
var key = kvpSplit.ElementAtOrDefault(0);
var value = kvpSplit.ElementAtOrDefault(1);
dictionary.Add(key, value);
// you may check with .ContainsKey if key is already persistant
// you may check if key and value with string.IsNullOrEmpty
}

If you know for sure that there are no separator chars in your input data, the following works
string input = "user=u123;name=Test;lastname=User";
string[] fragments = input.Split(";=".ToArray());
Dictionary<string,string> result = new Dictionary<string,string>()
for(int i=0; i<fragments.Length-1;i+=2)
result.Add(fragments[i],fragments[i+1]);
It might perform slightly better than some of the other solutions, since it only calls Split() once. Usually I would go for any of the other solutions here, especially if readability of the code is of any value to you.

I think I would do it like this...
String s = "user=u123;name=Test;lastname=User";
Dictionary<string,string> dict = s.ToDictionary();
The implementation of ToDictonary is the same as yours except that I would implement it as an extension method. It does look more natural.