在浏览器中执行以下代码时,它不会显示警报,它只是显示空白页面。以下代码中有任何问题请帮助我。
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text.html; charset=utf-8">
<title> First Program </title>
<link rel="stylesheet" type="text/css" href ="http://localhost:8080/ext/ext-4.2.1.883/resources/css/ext-all.css"/>
<script type = "text/javascript" src = "http://localhost:8080/ext/ext-4.2.1.883/ext-all-dev.js"/>
<script type="text/javascript">
Ext.onReady(function(){
// alert("We are ready to go!");
Ext.Msg.alert("Hello World");
});
</script>
</head>
<body>
</body>
</html>