1, JS verify whether Radio choose
<! DOCTYPE >
<Html>
<Head>
<Metahttp-equiv="Content-type"Content="Text/html; Charset=utf-8 ">
<Title>Untitled Document </Title>
<ScriptType="Text/javascript"Src="Js/jquery-2.2.2.min.js" >
</Script>
<ScriptType="Text/javascript" >
functionCheckform (obj) {
for (i=0; I<Obj.oo.length; I++)
if (Obj.oo[i].Checked= = True) {
return true;
}else {
Alert"Please select")
return false;
}
}
</Script>
</Head>
<Body>
<FormId="Form"Name="Form"Method="POST"action=""onsubmit="ReturnCheckform (This">
<InputType="Radio"Name="Oo"Value="RadioButton"/>Option One
<InputType="Radio"Name="oo" value="RadioButton"/> option two
<input type= name= "Submit"value= "Submission" />
</form>
</body>
</html>
2. length Limit
<Script>
functionTest () {
if (document.a.b.value.length>5) {
Alert"No more than 5 characters!" ");
Document.a.b.Focus ();
return false;
}
}
</Script>
<FormName=Aonsubmit="" >
<textarea name= "B" cols= "" wrap=rows= "6" onchange= "return test () "></textarea>
</FORM>
3, can only be Chinese characters
JS Form Validation