JavaScript dynamically judges HTML elements and performs different operations _javascript tips

In JavaScript, in order to perform different actions for different elements, you need to judge the elements that trigger the event in JavaScript, and then perform different actions.

Example:

Html

Copy Code code as follows:

<input type= ' button ' name= ' updatemetal ' value= ' modify ' onclick= ' Getmetalid (this) ' >
<input type= ' button ' name= ' deletemetal ' value= ' delete ' onclick= ' getmetalid (this) ' >

Javascript

Copy Code code as follows:

<script type= "Text/javascript" >
function Getmetalid (input) {
Metalid = Input.parentNode.parentNode.firstChild.innerHTML;
if (Input.getattribute ("value") = = ' Modify ') {
Damicsubmit (Metalid);
}else if (Input.getattribute ("value") = = ' Delete ') {
Damicsubmit2 (Metalid);
}
}
</script>

Getting the name and id attribute of input was unsuccessful, but value was OK, not knowing what the reason was.

Reference:

Copy Code code as follows:

var Obj=document.getelementbyid ("Div1"). getElementsByTagName ("textarea")
for (Var i=0;i<obj.length;i++)
{
if (obj[i].id== "AA")
{
Alert (Obj[i].innertext)
}
}