Develop Reference

C# - Split a string separated by ':'

Im trying to split this string:
PublishDate: "2011-03-18T11:08:07.983"
I tried Split method but it's not successful.
str.Split(new[] { ':', ' ' }, StringSplitOptions.RemoveEmptyEntries)
As a result I get PublishDate 2011-03-18T11 08 07.983
But correct result is PublishDate 2011-03-18T11:08:07.983
What i need to do?

Split(String, Int32, StringSplitOptions)
Splits a string into a maximum number of substrings based on a specified delimiting string and, optionally, options.
str.Split(':', 2, StringSplitOptions.RemoveEmptyEntries)
https://learn.microsoft.com/en-us/dotnet/api/system.string.split?view=net-6.0#system-string-split(system-string-system-int32-system-stringsplitoptions)

I would solve like this:
locate the index of the first :. The property name will be all the characters before this, which you can extract with Substring and Trim to remove whitespace before the colon, if present.
locate the index of the first " and last ". Characters between the first and last quotes are the property value.
string input = "PublishDate: \"2011-03-18T11:08:07.983\"";
int iColon = input.IndexOf(':');
int iOpenQuote = input.IndexOf('"', iColon);
int iCloseQuote = input.LastIndexOf('"');
string propertyName = input.Substring(0, iColon).Trim();
string propertyValue = input.Substring(iOpenQuote + 1, iCloseQuote - iOpenQuote - 1);
This does not handle escaped characters within the property value (for example, to embed a literal quote or newline using a typical escape sequence like \" or \n). But it's likely good enough to extract a date/time string, and permits all characters because of the use of LastIndexOf. However, this is not robust against malformed input, so you will want to add checks for missing colon, or missing quote, or what happens when the close quote is missing (same same index for start and end quote).

So if I got you right, you want as a result: PublishDate 2011-03-18T11:08:07.983.
Then I would recommend you to use the string.Replace method.
using System;
public class HelloWorld
{
public static void Main(string[] args)
{
string yourData = "PublishDate: \"2011-03-18T11:08:07.983\"";
// First replace the colon and the space after the PublishDate with and space
// then replace the quotes from the timestamp -> "2011-03-18T11:08:07.983"
yourData = yourData.Replace(": ", " ").Replace("\"", "");
// Output the result -> PublishDate 2011-03-18T11:08:07.983
Console.WriteLine(yourData);
}
}

How to replace all non-valid characters in string?

How would I go about in replacing every character in a string which are not the following:
abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789_.#-
with -
So for example, the name Danny D'vito would become DannyD-vito
My inital thought was converting string to char[] and looping through and checking each character, then convert back to string. But my hunch is telling me there must be an easier way to do this

Regex.Replace() approach
string input = "Danny D'vito";
string result = new Regex("[^a-zA-Z0-9_.#-]").Replace(input, "-");

To remove double quotes in string array

In the below code i have a string array which holds values like "1,2,3" i want to remove the double quotes and display as 1,2,3.pls help me to do this.
string[] Stocks = StockDetails.ToArray();
string s = string.Join(",", Stocks);

You can just use string.Replace
var listOfStrings = StockDetails.Select(s => s.Replace("\"", string.Empty))
.ToList();

If you're having string in this format
string str = "\"1,2,3\"";
..then you can simply remove the double quotation marks using Replace method on string.
str = str.Replace("\"", "");
..this will replace the double quotation from your string, and will return the simple text that is not a double quotes.
More I don't think strings are like this, you're having a look at the actual value of the variable string you're having. When you will use it, it will give you the actual 1, 2, 3 but however, use the above code to remove the quotation .

How to concatenate string with a backslash with another string

How can I concatenate the string "\u" with "a string" to get "\u0000"?
My code creates two backslashes:
string a = #"\u" + "0000"; //ends up being "\\\u0000";

The escape sequence \uXXXX is part of the language's syntax and represents a single Unicode character. By contrast, #"\u" and "0000" are two different strings, with a total of six characters. Concatenating them won't magically turn them into a single Unicode escape.
If you're trying to convert a Unicode code point into a single-character string, do this:
char.ConvertFromUtf32(strUnicodeOfMiddleChar).ToString()
BTW, don't use == true; it's redundant.

If I understand you correctly, I think you want to build a single-char string from an arbitrary Unicode value (4 hex digits). So given the string "0000", you want to convert that into the string "\u0000", i.e., a string containing a single character.
I think this is what you want:
string f = "0000"; // Or whatever
int n = int.Parse(f, NumberStyles.AllowHexSpecifier);
string s = ((char) n).ToString();
The resulting string s is "\u0000", which you can then use for your search.
(With corrections suggested by Thomas Levesque.)

the line below creates tow backslash:
string a = #"\u" + "0000"; //a ends up being "\\u0000";
No, it doesn't; the debugger shows "\" as "\", because that's how you write a backslash in C# (when you don't prefix the string with #). If you print that string, you will see \u0000, not \\u0000.

Nope, that string really has single backslash in. Print it out to the console and you'll see that.

Escape your characters correctly!!
Both:
// I am an escaped '\'.
string a = "\\u" + "0000";
And:
// I am a literal string.
string a = #"\u" + "0000";
Will work just fine. But, and I am going out on a limb here, I am guessing that you are trying to escape a Unicode Character and Hex value so, to do that, you need:
// I am an escaped Unicode Sequence with a Hex value.
char a = '\uxxxx';

How to remove a combination of characters from a string?

For Example, I am having a string like:
string str = "santhosh,ravi,phani,praveen,sathish,prakash";
Now , I need to remove ,phani from str.
can any one help me?
I tried by using trim and substring.but I am not getting that.

Try the following,
str = str.Replace(",phani", string.Empty);

You can use String.Replace() method for that;
Returns a new string in which all occurrences of a specified Unicode
character or String in the current string are replaced with another
specified Unicode character or String.
string str = "santhosh,ravi,phani,praveen,sathish,prakash";
str = str.Replace(",phani", "");
Console.WriteLine(str);
Here is a DEMO.