js dynamically adds onclick event that can pass parameters or not_javascript skills

1) When the method has no parameters, the value can be assigned directly using onclick = method name

window.onload = function() {
$('btnTest').onclick = test; 
}
function test() {
alert(val);
}

2) When the method has parameters, it is wrong to use onclick = method name (parameter). You need to add function()

in front of the method name.

window.onload = function() {
$('btnTest').onclick= function() { test(1) }; 
}
function test(val) {
alert(val);
}