How do I trigger a function from a string?
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How to execute a JavaScript function when I have its name as a string
I have this function
function myfunc() {
alert('it worked!');
}
and this variable which is a string
var callback = 'myfunc';
How do I trigger the function from that string?
Assuming that the function is declared globally it will be contained in the window object so you can call it using window[callback]() .
Globally declared functions are stored in the window object so you would be able to reference myfunc using window.myfunc . As with other properties on JavaScript objects you can use the brace syntax instead of the dot notation which would be window["myfunc"] since you have the string "myfunc" contained in your callback variable you can simply use that instead. Once you have the reference you call it as a function which gives window[callback]() .
If you're doing this in browser, try this: window[callback]()
It is also possible to use eval — something like eval(callback + '()') — but this is very inefficient and not recommended.
Also, you may want to consider assigning the function itself instead of its name to the callback variable:
function myfunc() {...}
var callback = myfunc
...
callback() # trigger callback
This would work in many cases, but of course, sometimes you just need to pass it as a string.
If this is code running on the browser, then myfun is a method of the window object. You can invoke the method like so:
window[callback]();
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