C# Strings

In this lesson, you will learn about Strings in C#, string operations, and examples to better understand the topic.

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String in C#

A string variable is a collection of characters inside a double quote. For example:

string name = "John";

Strings are used to store Alphanumeric values. They are immutable, which means they cannot be changed once created. Instead, a new string object is created in the memory to store the new value.

Manipulating a string too many times may result in a performance issue. For this purpose, we can use the String Builder Class, which we discuss later in this course.

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String Built-in Methods

The string type contains useful built-in functions. Below are some of the string functions that most developers should be aware of:

String Lenght

To return the length of a string, you can simply use the Length method as shown in the example below:

String ToUpper

Another useful method in the string type is the ToUpper() method, which transforms the string characters into uppercase letters. Example:

String ToLower

The ToLower() method is the opposite of the ToUpper(); it transforms all the characters in a string into Lowercase letters. Example:

String Concat

The Concat method Concat two strings or more into one string. Example:

Another way to contact string in C# is to use the + Operator. For Example:

String IndexOf

This method returns an integer value of the index position of a given character in a string. For Example:

String Substring

The Substring method extracts characters from a string, starting from the index, and returns the result in a new string object. For Example:

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Accessing a String

Since a string variable is a collection of characters, you can access a specific character by referring to its index, starting from position 0. For example

You can access the characters in a string by referring to its index number inside square brackets [].

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String and Special characters

As we already know, strings are surrounded by two double Quote “”. But what if the string itself contains double quotes? Example:

string myString = "I am studying "C#" using a great course!";

The string “C#” will confuse the compiler and generate an error. In this case, we add the backslash \ to escape the special character right before each double-quote. Example:

The escaping character is useful for strings containing double quotes “, single quotes, and backslashes. For Example:

Also, the C# programming language offers more escaping characters, as shown in the example below:

This concludes the C# Strings lesson. In the next lesson, you will learn about the StringBuilder Class in C#.