JS_HasInstance 编辑

JSAPI method equivalent to the instanceof operator in JavaScript.

Syntax

bool
JS_HasInstance(JSContext *cx, JS::Handle<JSObject*> obj, JS::Handle<JS::Value> v, bool *bp);

Description

JS_HasInstance determines if a specified JS value, v, is an instance of JS object, obj. This function is equivalent to v instanceof obj test in JavaScript. On success, JS_HasInstance stores the result of the instanceof test in *bp and returns true. On error or exception, it returns false, and the value left in *bp is undefined.

When providing a prototype as obj, the prototype's JSClass must have its hasInstance method set. Otherwise JS_HasInstance returns false.

See Also

• MXR ID Search for JS_HasInstance
• JS_InstanceOf