Redaguoti

Dalintis per

bool (C# reference)

The bool type keyword is an alias for the .NET System.Boolean structure type that represents a Boolean value, which can be either true or false.

The C# language reference documents the most recently released version of the C# language. It also contains initial documentation for features in public previews for the upcoming language release.

The documentation identifies any feature first introduced in the last three versions of the language or in current public previews.

Tip

To find when a feature was first introduced in C#, consult the article on the C# language version history.

To perform logical operations with values of the bool type, use Boolean logical operators. The bool type is the result type of comparison and equality operators. A bool expression can be a controlling conditional expression in the if, do, while, and for statements and in the conditional operator ?:.

The default value of the bool type is false.

Literals

Use the true and false literals to initialize a bool variable or to pass a bool value:

bool check = true;
Console.WriteLine(check ? "Checked" : "Not checked");  // output: Checked

Console.WriteLine(false ? "Checked" : "Not checked");  // output: Not checked

Three-valued Boolean logic

Use the nullable bool? type if you need to support three-valued logic. For example, use it when you work with databases that support a three-valued Boolean type. For the bool? operands, the predefined & and | operators support the three-valued logic. For more information, see the Nullable Boolean logical operators section of the Boolean logical operators article.

For more information about nullable value types, see Nullable value types.

Conversions

C# provides only two conversions that involve the bool type. Those conversions are an implicit conversion to the corresponding nullable bool? type and an explicit conversion from the bool? type. However, .NET provides additional methods that you can use to convert to or from the bool type. For more information, see the Converting to and from Boolean values section of the System.Boolean API reference page.

C# language specification

For more information, see The bool type section of the C# language specification.

See also

  • Last updated on