1) When the method has no parameters, the value can be assigned directly using onclick = method name
Copy the code code as follows:
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.
Copy the code code as follows:
window.onload = function() {
$('btnTest').onclick = function() { test(1) };
}
function test(val) {
alert(val);
}