JavaScript Learning Journey (3)_Basic Knowledge

childNodes attribute: will return an array containing all child elements of the given element node.
childType attribute: The returned array contains all types of nodes
nodeValue attribute: change the value of a text node
firstChild and lastChild attributes: whenever and wherever, as long as you need to access the childNodes[] array The first element can be written as firstChild outside.
node.firstChild is equivalent to node.childNodes[0]
Similarly
node.lastChild is equivalent to node.childNodes[node.childNodes.length-1]

Chapter 5 JavaScript programming principles and good habits

Reserve a fallback route
Separate javascript
Backward compatibility

Chapter 6

Bind multiple javascript functions to onload On the event handler function

function addLoadEvent(func){
varoldonload=window.onload;
if(typeof window.onload!='function'){
windows.onload=func;
}
else{
window.onload=function(){
oldonload();
func();
}
}
}


Call method
addLoadEvent(method name);
addLoadEvent(method name);