AJAX在线基础(四(基础完))

最新推荐文章于 2024-11-07 01:22:08 发布

why7282

最新推荐文章于 2024-11-07 01:22:08 发布

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CC 4.0 BY-SA版权

文章标签： Ajax Microsoft HTML

本文链接：https://blog.youkuaiyun.com/why7282/article/details/83909522

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">

<html>
<head>
<title>Ajax Auto Complete</title>
<style type="text/css">

.mouseOut {
background: #708090;
color: #FFFAFA;
}

.mouseOver {
background: #FFFAFA;
color: #000000;
}
</style>
<script type="text/javascript">
var xmlHttp;
var completeDiv;
var inputField;
var nameTable;
var nameTableBody;

function createXMLHttpRequest() {
if (window.ActiveXObject) {
xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
}
else if (window.XMLHttpRequest) {
xmlHttp = new XMLHttpRequest();
}
}

function initVars() {
inputField = document.getElementById("names");
nameTable = document.getElementById("name_table");
completeDiv = document.getElementById("popup");
nameTableBody = document.getElementById("name_table_body");
}

function findNames() {
initVars();
if (inputField.value.length > 0) {
createXMLHttpRequest();
var url = "AutoCompleteServlet?names=" + escape(inputField.value);
xmlHttp.open("GET", url, true);
xmlHttp.onreadystatechange = callback;
xmlHttp.send(null);
} else {
clearNames();
}
}

function callback() {
if (xmlHttp.readyState == 4) {
if (xmlHttp.status == 200) {
var name = xmlHttp.responseXML.getElementsByTagName("name")[0].firstChild.data;
setNames(xmlHttp.responseXML.getElementsByTagName("name"));
} else if (xmlHttp.status == 204){
clearNames();
}
}
}

function setNames(the_names) {
clearNames();
var size = the_names.length;
setOffsets();

var row, cell, txtNode;
for (var i = 0; i < size; i++) {
var nextNode = the_names[i].firstChild.data;
row = document.createElement("tr");
cell = document.createElement("td");

cell.onmouseout = function() {this.className='mouseOver';};
cell.onmouseover = function() {this.className='mouseOut';};
cell.setAttribute("bgcolor", "#FFFAFA");
cell.setAttribute("border", "0");
cell.onclick = function() { populateName(this); } ;

txtNode = document.createTextNode(nextNode);
cell.appendChild(txtNode);
row.appendChild(cell);
nameTableBody.appendChild(row);
}
}

function setOffsets() {
var end = inputField.offsetWidth;
var left = calculateOffsetLeft(inputField);
var top = calculateOffsetTop(inputField) + inputField.offsetHeight;

completeDiv.style.border = "black 1px solid";
completeDiv.style.left = left + "px";
completeDiv.style.top = top + "px";
nameTable.style.width = end + "px";
}

function calculateOffsetLeft(field) {
return calculateOffset(field, "offsetLeft");
}

function calculateOffsetTop(field) {
return calculateOffset(field, "offsetTop");
}

function calculateOffset(field, attr) {
var offset = 0;
while(field) {
offset += field[attr];
field = field.offsetParent;
}
return offset;
}

function populateName(cell) {
inputField.value = cell.firstChild.nodeValue;
clearNames();
}

function clearNames() {
var ind = nameTableBody.childNodes.length;
for (var i = ind - 1; i >= 0 ; i--) {
nameTableBody.removeChild(nameTableBody.childNodes[i]);
}
completeDiv.style.border = "none";
}

</script>
</head>
<body>
<h1>谷歌定位</h1>
搜索 <input type="text" size="20" id="names" onkeyup="findNames();" style="height:20;"/>
<div style="position:absolute;" id="popup">
<table id="name_table" bgcolor="#FFFAFA" border="0" cellspacing="0" cellpadding="0"/>
<tbody id="name_table_body"></tbody>
</table>
</div>
</body>
</html>

实现思路：利用键盘输入的完结响应时间，从后来获取数据，然后解析数据进行显示，其中有很多需要注意的小细节的地方。本例子来源于AJAX基础教程书籍