Why is window.onload function undefined?

Question

I have made a simple function and it is supposed to run on window.onload. But instead, I get that it is undefined. Can anyone help me understand why I get this error?

The form id is kalkulator and the name of the inputs is liter and enheter

The function I have written is

window.onload = function () {
    form.kalkulator.focus();
};

I have also written this

form.kalkulator = function () {
    if (form.enheter.value == "") {
        form.liter.value = "";
    } else{
        convertLiter();
    };
}

function convertLiter() {
    console.log(form.liter.value / person.volum() * person.sukker_g())
    form.enheter.value = form.liter.value / person.volum();

}
function convertEnheter() {
    console.log(form.enheter.value * person.sukker_g())
    form.liter.value = form.enheter.value * person.volum();
}

Have a look here: http://stackoverflow.com/a/4331028/2180252 — Niddro, Mar 01 '15 at 14:37

score 0 · Answer 1 · answered Mar 01 '15 at 14:27

0

This has nothing to do with window.onload.

You're invoking this...

form.kalkulator.focus();

but form.kalkulator is a function, it doesn't have a .focus() method. form.klalkulator.focus is undefined, and you're attempting to invoke it as a function, hence your error.

answered Mar 01 '15 at 14:27

user229044

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@user262669 Don't write that line of code. I have no idea what you're actually trying to do. – user229044 Mar 01 '15 at 14:30

score 0 · Answer 2 · answered Mar 01 '15 at 14:28

form.kalkulator doesn't have any return so you can't call

  form.kalkulator.focus();

replace the function

form.kalkulator = function () {
    if (form.enheter.value == "") {
        form.liter.value = "";
    } else{
        convertLiter();
   };
return form;
}

or split the instructions;

form.kalkulator();
form.focus();

Why is window.onload function undefined?

2 Answers2