JS_ValueToObject 编辑

Converts any JavaScript value to an object.

Syntax

bool
JS_ValueToObject(JSContext *cx, JS::HandleValue v, JS::MutableHandleObject objp);

Description

JS_ValueToObject converts a specified JavaScript value, v, to an object. On success, this function stores either NULL or a pointer to the resulting object in *objp and returns true. Otherwise it returns false and the value left in *objp is unspecified.

• If v is JSVAL_NULL or JSVAL_VOID, the result is NULL.
• If v is a boolean value, a number, or a string, the result is a new wrapper object of type Boolean, Number, or String.
• Otherwise v is an object, and the result depends on the object. If v is a native JavaScript Object, this calls the object's valueOf method, if any. In any case, the result is not guaranteed to be the same object as v. (Implementation note: the object's JSObjectOps.defaultValue method is called with hint=JSTYPE_OBJECT.)

The resulting object is subject to garbage collection unless the variable *objp is protected by a local root scope, an object property, or the JS_AddRoot function. Note that a local root scope is not sufficient to protect the resulting object in some cases involving the valueOf method!

See Also

• MXR ID Search for JS_ValueToObject
• JS_ConvertArguments
• JS_ConvertValue
• JS_TypeOfValue
• JS_ValueToFunction