This documentation is archived and is not being maintained.

OpCodes.Brfalse_S Field

Transfers control to a target instruction if value is false, a null reference, or zero.

[Visual Basic]
Public Shared ReadOnly Brfalse_S As OpCode
[C#]
public static readonly OpCode Brfalse_S;
[C++]
public: static OpCode Brfalse_S;
[JScript]
public static var Brfalse_S : OpCode;

Remarks

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
2C < int8 > brfalse.s target

brnull.s target

brzero.s target

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

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.s 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 *, natural int) is zero (false). If value is non-zero (true) execution continues at the next instruction.

The target instruction is represented as a 1-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 constructor overload can use the brfalse.s opcode:

  • ILGenerator.Emit(OpCode, Label)

Requirements

Platforms: Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 family

See Also

OpCodes Class | OpCodes Members | System.Reflection.Emit Namespace

Show: