Entry: JS_ValueToECMAInt32 (Function)
Summary: Converts a JS value to an ECMA-compliant 32-bit integer.
Syntax:
JSBool JS_ValueToECMAInt32(JSContext *cx, jsval v, int32 *ip);
Argument Type Description
cx JSContext * Pointer to a JS context from which to derive runtime information.
v jsval The JS value to convert.
ip int32 * Pointer to the JS value that contains the converted integer when the function returns.
Description:
JS_ValueToECMAInt32 converts a JS value, v, to a JS double, and then to an ECMA-standard, 32-bit, signed integer. The fractional portion of the double is dropped silently during conversion to an integer value. If the double is out of range, the result is computed modulo 2**32; if the result is then greater than or equal to 2**31, this function subtracts 2**32, yielding a negative result.
You can convert a JS value to an integer if the JS value to convert is a JSVAL_INT, JSVAL_DOUBLE, or JSVAL_BOOLEAN. If the JS value is a JSVAL_STRING that contains a well formed numeric literal (ignoring leading and trailing whitespace) conversion also succeeds. If the JS value is a JSVAL_OBJECT, conversion is successful if the object's convert operation returns a primitive value that can be converted.
If the conversion is successful, JS_ValueToECMAInt32 returns JS_TRUE. Otherwise, it reports an error and returns JS_FALSE.
See also:
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