一个简单的AJAX与JSP示例

use*_*abh 10 java ajax jsp asynchronous

我正在尝试用JSP学习AJAX,我编写了以下代码.这似乎不起作用.请帮忙:

这是我的configuration_page.jsp

    <html>
     <head>
     <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
     <title>JSP Page</title>
     <script type="text/javascript">

      function loadXMLDoc()
      {
        var xmlhttp;
        var config=document.getElementById('configselect').value;
        var url="get_configuration.jsp";
        if (window.XMLHttpRequest)
        {
            xmlhttp=new XMLHttpRequest();
        }
        else
        {
            xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
        }
        xmlhttp.onreadystatechange=function()
        {
            if (xmlhttp.readyState==4 && xmlhttp.status==200)
            {
                document.getElementById("myDiv").innerHTML=xmlhttp.responseText;
            }
        }

        xmlhttp.open("GET", url, true);
        xmlhttp.send();
}
</script>        

</head>

<body>
  <h2 align="center">Saved Configurations</h2>
   Choose a configuration to run: 
  <select name="configselect" width="10">
    <option selected value="select">select</option>
    <option value="Config1">config1</option>
    <option value="Config2">config2</option>
    <option value="Config3">config3</option>
  </select> 
  <button type="button" onclick='loadXMLDoc()'> Submit </button>
  <div id="myDiv">
    <h4>Get data here</h4>
  </div>
 </body>
</html>
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这是我的get_configuration.jsp,我试图从上面的AJAX代码访问:

<html>
  <head>
      <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
      <title>JSP Page</title>

  </head>
  <body>

    <h4>Mee..</h4> 
  </body>
</html>
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小智 14

我使用jQuery AJAX来发出AJAX请求.

检查以下代码:

<html>
<head>
    <script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.4/jquery.min.js"></script>
    <script type="text/javascript">
        $(document).ready(function() {
            $('#call').click(function ()
            {
                $.ajax({
                    type: "post",
                    url: "testme", //this is my servlet
                    data: "input=" +$('#ip').val()+"&output="+$('#op').val(),
                    success: function(msg){      
                            $('#output').append(msg);
                    }
                });
            });

        });
    </script>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
    <title>JSP Page</title>
</head>
<body>
    input:<input id="ip" type="text" name="" value="" /><br></br>
    output:<input id="op" type="text" name="" value="" /><br></br>
    <input type="button" value="Call Servlet" name="Call Servlet" id="call"/>
    <div id="output"></div>
</body>
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Pra*_*rma 2

您在“configuration_page.jsp”文件中犯了错误。在此文件中,函数 loadXMLDoc() 的第 2 行应如下所示:

var config=document.getElementsByName('configselect').value;
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name因为您只在标记中声明了该属性<select>。所以你应该通过名称来获取这个元素。

更正此问题后,它将运行而不会出现任何 JavaScript 错误