Is there a way to handle undefined functions being called in JavaScript?

拟墨画扇 提交于 2019-12-22 04:36:11

问题


If I have a function like the following:

function catchUndefinedFunctionCall( name, arguments )
{
    alert( name + ' is not defined' );
}

and I do something silly like

foo( 'bar' );

when foo isn't defined, is there some way I can have my catch function called, with name being 'foo' and arguments being an array containing 'bar'?


回答1:


There is in Mozilla Javascript 1.5 anyway (it's nonstandard).

Check this out:

var myObj = {
    foo: function () {
        alert('foo!');
    }
    , __noSuchMethod__: function (id, args) {
        alert('Oh no! '+id+' is not here to take care of your parameter/s ('+args+')');
    } 
}
myObj.foo();
myObj.bar('baz', 'bork'); // => Oh no! bar is not here to take care of your parameter/s (baz,bork)

Pretty cool. Read more at https://developer.mozilla.org/en/Core_JavaScript_1.5_Reference/Global_Objects/Object/NoSuchMethod




回答2:


try {
 foo();
}
catch(e) {
   callUndefinedFunctionCatcher(e.arguments);
}

UPDATED

passing e.arguments to your function will give you what you tried to pass originally.




回答3:


someFunctionThatMayBeUndefinedIAmNotSure ? someFunctionThatMayBeUndefinedIAmNotSure() : throw new Error("Undefined function call");


来源:https://stackoverflow.com/questions/2527474/is-there-a-way-to-handle-undefined-functions-being-called-in-javascript

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