Casting and Converting Between Types

We will often need to convert the values of variables between different types. For example, data input is usually entered as text at the console, initially stored in a string type variable. Still, depending on how it should be stored and processed, it must be converted into a date/time, number, or other data type. Sometimes, we must convert between number types, like an integer and a floating point, before calculating.

Casting

Converting, also known as casting, has two varieties: implicit and explicit.

• Implicit casting: Happens automatically and is safe, meaning we will not lose any information.

• Explicit casting: This must be performed manually because it may lose information, such as a number's precision. By explicitly casting, we tell the C# compiler we understand and accept the risk.

Casting numbers implicitly and explicitly

Implicitly casting an int variable into a double variable is safe because no information can be lost, as the following shows:

Step 1: Use your preferred coding tool to add a new "Console App or console project" named CastingConverting to the Chapter03 workspace/solution.

• In Visual Studio Code, select CastingConverting as the active OmniSharp project.

Step 2: In the Program.cs, delete the existing statements and then type statements to declare and assign an int variable and a double variable, and then implicitly cast the integer’s value when assigning it to the double variable, as shown in the following code: