CSHARP

c# get first 5 characters of string

string result = str.Substring(0,5);

c# get the first 4 characters in the list

            //get the 4 characters from the List of string
           // first convert the list into a string
            string result = string.Join("", lstData.ToArray());
          // now you can use the substring function
            var finalResult = result.Substring(0, 4);