In addition to many built-in value types, like the numeric types, C# provides a built-in string type. The string type is a reference type, equivalent to the .NET Framework System.String type.
Strings contain a sequence of Unicode (UTF16) characters, equivalent to an array of char. Each character takes up exactly 2 bytes.
Strings are immutable, which means that you can’t change a string’s value without destroying the old string and creating a new one.
You can use the index operator [] to access individual characters in the string. This will normally give you a single character, except for Unicode characters that are above U+FFFF and have to be represented using a surrogate pair.
Here are some examples:
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| string msg = "We Love C#!"; char fourth = msg[3]; string thisnthat = "this" + "that"; // "thisthat"string sub = msg.Substring(3, 4); // "Love" string dash = msg.Replace(' ', '-'); // "We-Love-C#!" // Split into space-delimited words: "We", "Love", "C#!" string[] words = msg.Split(new char[]{' '}); string concat = msg + " Yes we do."; bool foundLove = words[1].ToLower() == "love"; // Convert to lowercase, find substring int findLove = msg.ToLower().IndexOf("love"); // Iterate foreach (char c in msg) Console.Write(string.Format("{0}-", c)); string newPtr = msg; // Pointer to original string string new2 = String.Copy(msg); // Creates new string instance msg = "change"; // But newPtr still pointing to old/orig string |