Interlocked.CompareExchange Method (Int64, Int64, Int64)


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Compares two 64-bit signed integers for equality and, if they are equal, replaces the first value.

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

public static long CompareExchange(
	ref long location1,
	long value,
	long comparand


Type: System.Int64

The destination, whose value is compared with comparand and possibly replaced.

Type: System.Int64

The value that replaces the destination value if the comparison results in equality.

Type: System.Int64

The value that is compared to the value at location1.

Return Value

Type: System.Int64

The original value in location1.

Exception Condition

The address of location1 is a null pointer.

If comparand and the value in location1 are equal, then value is stored in location1. Otherwise, no operation is performed. The compare and exchange operations are performed as an atomic operation. The return value of CompareExchange is the original value in location1, whether or not the exchange takes place.

Universal Windows Platform
Available since 8
.NET Framework
Available since 2.0
Portable Class Library
Supported in: portable .NET platforms
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1
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