C sharp - Common String Methods in C#

What is a String in C#?

A string in C# is a sequence of characters enclosed in double quotes ("). It's an object of the System.String class, which provides many built-in methods to manipulate and work with text.

Common String Methods in C#

1. Length – Get the number of characters

string name = "Hello";
Console.WriteLine(name.Length);  // Output: 5

2. ToUpper() and ToLower() – Convert case

string name = "ChatGPT";
Console.WriteLine(name.ToUpper()); // Output: CHATGPT
Console.WriteLine(name.ToLower()); // Output: chatgpt

3. Substring() – Get part of the string

string message = "Hello World";
Console.WriteLine(message.Substring(6));    // Output: World
Console.WriteLine(message.Substring(0, 5)); // Output: Hello

4. IndexOf() – Find character or word index

string text = "C# Programming";
Console.WriteLine(text.IndexOf("g")); // Output: 6

 5. Contains() – Check if text exists

string sentence = "Learn C# with examples";
Console.WriteLine(sentence.Contains("C#")); // Output: True

 6. Replace() – Replace part of string

string sentence = "I like Java";
Console.WriteLine(sentence.Replace("Java", "C#")); // Output: I like C#

7. Trim() – Remove whitespace

string userInput = "  Hello  ";
Console.WriteLine(userInput.Trim()); // Output: "Hello"

 8. Split() – Break string into words

string fruits = "Apple,Banana,Cherry";
string[] result = fruits.Split(',');

foreach (string fruit in result)
{
    Console.WriteLine(fruit);
}

Output:

Apple
Banana
Cherry

9. Equals() – Compare strings

string a = "hello";
string b = "Hello";

Console.WriteLine(a.Equals(b));                // False (case-sensitive)
Console.WriteLine(a.Equals(b, StringComparison.OrdinalIgnoreCase)); // True