代码示例：（标识：demo_php_ajax_mysql）
<!doctype html>
<html>
<head>
<script>
function showUser(str) {
if (str=="") {
document.getElementById("txtHint").innerHTML="";
return;
}
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 (this.readyState==4 && this.status==200) {
document.getElementById("txtHint").innerHTML=this.responseText;
}
}
xmlhttp.open("GET","/static/demo/php/getcustomer.php?q="+str,true);
xmlhttp.send();
}
</script>
</head>
<body>
<form>
<select name="users" onchange="showUser(this.value)">
<option value="">请选择一个客户：</option>
<option value="1">Alibaba</option>
<option value="2">APPLE</option>
<option value="3">BAIDU</option>
<option value="4">Canon</option>
<option value="5">Google</option>
<option value="6">HUAWEI</option>
<option value="7">Microsoft</option>
<option value="8">Nokia</option>
<option value="9">SONY</option>
<option value="10">Tencent</option>
</select>
</form>
<br>
<div id="txtHint"><b>客户信息将在此处列出。</b></div>
</body>
</html>
