AJAX exampleLOGIN

AJAX example

Let’s look at an example first:

<!DOCTYPE html>
<html>
<head>
<script>
function loadXMLDoc()
{
    var xmlhttp;
    if (window.XMLHttpRequest)
      {// code for IE7+, Firefox, Chrome, Opera, Safari
      xmlhttp=new XMLHttpRequest();
      }
    else
      {// code for IE6, IE5
      xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
      }
     xmlhttp.onreadystatechange=function()
      {
      if (xmlhttp.readyState==4 && xmlhttp.status==200)
        {
        document.getElementById("myDiv").innerHTML=xmlhttp.responseText;
        }
      }
    xmlhttp.open("GET","/try/ajax/ajax_info.txt",true);
    xmlhttp.send();
}
</script>
</head>
<body>
<div id="myDiv"><h2>使用 AJAX 修改该文本内容</h2></div>
<button type="button" onclick="loadXMLDoc()">修改内容</button>
</body>
</html>


##Example analysis

The above AJAX application Contains a div and a button. The

div section is used to display information from the server. When the button is clicked, it is responsible for calling a function called loadXMLDoc():

<!DOCTYPE html>
<html>
<body>
  <div id="myDiv"><h2>Let AJAX change this text</h2></div>
  <button type="button" onclick="loadXMLDoc()">Change Content</button>
</body>
</html>

Next, add a <script> tag to the head section of the page. This tag contains the loadXMLDoc() function:

<head>
<script>
    function loadXMLDoc()
    {
    .... AJAX script goes here ...
    }
</script>
</head>

Note: ajax_info.txt and HTML files need to be placed under the same virtual host or the same website to run.
Next Section

<!DOCTYPE html> <html> <head> <script> function loadXMLDoc() { var xmlhttp; if (window.XMLHttpRequest) {// code for IE7+, Firefox, Chrome, Opera, Safari xmlhttp=new XMLHttpRequest(); } else {// code for IE6, IE5 xmlhttp=new ActiveXObject("Microsoft.XMLHTTP"); } xmlhttp.onreadystatechange=function() { if (xmlhttp.readyState==4 && xmlhttp.status==200) { document.getElementById("myDiv").innerHTML=xmlhttp.responseText; } } xmlhttp.open("GET","/asset/demo.ajax.php?dm=txt",true); //注意路径的引用 xmlhttp.send(); } </script> </head> <body> <div id="myDiv"><h2>使用 AJAX 修改该文本内容</h2></div> <button type="button" onclick="loadXMLDoc()">修改内容</button> </body> </html>
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