Interlocked.Increment Method (Int64%)

Increments a specified 64-bit signed integer variable and stores the result, as an atomic operation.

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


Public Shared Function Increment ( _
    ByRef location As Long _
) As Long
public static long Increment(
    ref long location


  • location
    Type: System.Int64%
    The variable whose value is to be incremented.

Return Value

Type: System.Int64
The incremented value.


Exception Condition

The address of location is a null pointer.


This method handles an overflow condition by wrapping: If location = Int64.MaxValue, location + 1 = Int64.MinValue. No exception is thrown.

The 64-bit overloads of the Increment, Decrement, and Add methods are truly atomic only on systems where a System.IntPtr is 64 bits long. On other systems, these methods are atomic with respect to each other, but not with respect to other means of accessing the data. Thus, to be thread safe on 32-bit systems, any access to a 64-bit value must be made through the members of the Interlocked class.

Version Notes

Silverlight for Windows Phone Silverlight for Windows Phone

 64-bit members of the Interlocked class are present but not supported.

Version Information


Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

XNA Framework

Supported in: Xbox 360, Windows Phone OS 7.0


For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.