MACROMEDIA Flash Lite 2, Справочник

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Operators 133
The following example converts -1 to a 32-bit integer and shifts it 1 bit to the right:
var x:Number = -1 >> 1;
trace(x); // outputs -1
The following example shows the result of the previous example:
var x:Number = -1;
This is because -1 decimal equals 11111111111111111111111111111111 binary (thirty-two
1s), shifting right by one bit causes the least significant (bit farthest to the right) to be
discarded and the most significant bit to be filled in with 1. The result is
11111111111111111111111111111111 (thirty-two 1s) binary, which represents the 32-bit
integer -1.
See also
>>= bitwise right shift and assignment operator
>>= bitwise right shift and assignment operator
expression1 >>= expression2
This operator performs a bitwise right-shift operation and stores the contents as a result in
expression1
.
The following two statements are equivalent:
A >>= B; and A = (A >> B);
Availability: ActionScript 1.0; Flash Lite 2.0
Operands
expression1 : Number
- A number or expression to be shifted right.
expression2 : Number
- A number or expression that converts to an integer from 0 to 31.
Returns
Number
- The result of the bitwise operation.
Example
The following commented code uses the bitwise right shift and assignment (
>>=
) operator.
function convertToBinary(numberToConvert:Number):String {
var result:String = "";
for (var i = 0; i<32; i++) {
// Extract least significant bit using bitwise AND
var lsb:Number = numberToConvert & 1;
// Add this bit to the result