Expand Minimize

OpCodes.Brfalse Field

Transfers control to a target instruction if value is false, a null reference (Nothing in Visual Basic), or zero.

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

public static readonly OpCode Brfalse

The following table lists the instruction's hexadecimal and Microsoft Intermediate Language (MSIL) assembly format, along with a brief reference summary:

Format

Assembly Format

Description

39 < int32 >

brfalse target

brnull target

brzero target

Branches to a target instruction at the specified offset if false.

The stack transitional behavior, in sequential order, is:

  1. value is pushed onto the stack by a previous operation.

  2. value is popped from the stack; if value is false, branch to target.

The brfalse instruction (and its aliases brnull and brzero) transfers control to the specified target instruction if value (of type int32, int64, object reference O, managed pointer &, transient pointer *, native int) is zero (false). If value is non-zero (true) execution continues at the next instruction.

The target instruction is represented as a 4-byte signed offset from the beginning of the instruction following the current instruction.

Control can only be transferred to the first of these prefixes if the target instruction has one or more prefix codes. Control transfers into and out of try, catch, filter, and finally blocks cannot be performed by this instruction.

The following Emit method overload can use the brfalse opcode:

  • ILGenerator.Emit(OpCode, Label)

.NET Framework

Supported in: 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
Was this page helpful?
(1500 characters remaining)
Thank you for your feedback

Community Additions

ADD
Show:
© 2014 Microsoft