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String.IsNullOrEmpty Method

Indicates whether the specified string is a null reference (Nothing in Visual Basic) or an Empty string.

Namespace:  System
Assembly:  mscorlib (in mscorlib.dll)

static member IsNullOrEmpty : 
        value:string -> bool

Parameters

value
Type: System.String

The string to test.

Return Value

Type: System.Boolean
true if the value parameter is a null reference (Nothing in Visual Basic) or an empty string (""); otherwise, false.

IsNullOrEmpty is a convenience method that enables you to simultaneously test whether a String is a null reference (Nothing in Visual Basic) or its value is Empty. It is equivalent to the following code:

No code example is currently available or this language may not be supported.

You can use the IsNullOrWhiteSpace method to test whether a string is a null reference (Nothing in Visual Basic), its value is String.Empty, or it consists only of white-space characters.

The following example examines three strings and determines whether each string has a value, is an empty string, or is a null reference (Nothing in Visual Basic).

No code example is currently available or this language may not be supported.

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

XNA Framework

Supported in: 3.0, 2.0, 1.0

.NET for Windows Phone apps

Supported in: Windows Phone 8.1, Windows Phone Silverlight 8.1, Windows Phone Silverlight 8

Portable Class Library

Supported in: Portable Class Library
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