The example in this article describes the method of obtaining form in js. Share it with everyone for your reference. The details are as follows:
Let’s look at the following code first:
<html>
<head>
<scirpy>
window.onload=function(){
var f1=document.f1;
var f2=document.forms[1];
alert(f2.id);
var f3=document.forms['f1'];
}
</script>
</head>
<body>
<form id="f1" value="f1"></from>
<from id="f2" value="f2"></form>
</body>
</html>Operation form:
<html>
<head>
<script>
function checkform(f){
var uname=f.username;
var pwd=f.password;
if(uname.value.length<4){
alert('用户长度必须大于4')；
return false;
}
if(pwd.value.length!=6){
alert('用户密码必须大于 6位');
return false;
}
return true;
}
</script>
</head>
<body>
<form id="f1" name="f1" method="post" action=""
onsubmit="return checkform(this)">
<input name="username" value="" /></br>
<input name="password" value="" /></br>
<input type="button" value="提交" />
</form>
</body>
</html>Three ways to operate forms with js:
1. Use the index of the form in the document or the name attribute of the form to reference the form
2. Use the id attribute of the form
3.
I hope this article will be helpful to everyone’s JavaScript programming design.
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