javascript

JQuery selectors in small problems of newcomers inevitably encountered

Today, according to the jQuery manual to learn, understand the use of the selector, ready to try to write a user registration verification, did not expect to have not started a small problem stumped me!

New appointees inevitably encounter small details, in this article only for self-encouragement:

The test code is as follows:


<script type="text/javascript" src="jquery.1.11.0.min.js"></script>
<script type="text/javascript">

function checkUser(){ //Check the username function
alert("OK"); //Test...
}

$(document).ready(function(){

$(":text :first").blur(function (){ //Something that triggers when you lose focus

  Right!!! When using hierarchical combination selectors, there are Spaces between them
checkUser();

});

</script>

</head>
<body>

<form>
<fieldset>
<legend> The sign-up page </legend>
 The user name <input type="text"> <br>
 password <input type="password"><span> <br>
 Verify password <input type="password"> <br>
email<input type="text" ><span> <br>
<input type="submit" value=" registered ">
</fieldset>
</form>

</body>
</html>