Why window.addEventListener does not work?
This question already has an answer here:
While you using var x = function(){} to declare functions, it should be declare before you call the function.
By function x (){} , x will exist in current scope, no matter how later it declare. Because such side effect , the var x = function(){} are more recommended. For example:
var user = 'alien';
if( user == 'alien') {
function salute () { console.log("Welcome to Earth!"); }
} else {
function salute (){ console.log("Good day!"); }
}
The salute() will print Good day! anyway, even though it not we want at all.
Declare the function before.
var initialiseTable = function () {
console.log("hello world!!");
};
try {
window.addEventListener("load", initialiseTable, false);
} catch(e) {
window.onload = initialiseTable;
}
For more information about declaring a function read this: var functionName = function() {} vs function functionName() {}
Since you come from C#, the difference is a lot like:
class A {
public int method2() {
//I can call method1 even though it *declared* later below
int a = method1();
}
public int method1() {
}
}
vs
class B {
public int method2() {
bool a = method1(3); //I can't call it because it is *assigned* later below.
//In fact I cannot even compile it
Func<int, bool> method1 = x => x == 3;
}
}
You may notice the difference in javascript, if you look at:
function a() {
}
There is no assignment anywhere.
Where as with var a = function(){} there is obviously assignment and it is similar to the latter C# example.
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