常用JavaScript代码10
157.定位鼠标
document.all.hint_layer.style.left = event.x+document.body.scrollLeft+10;
document.all.hint_layer.style.top = event.y+document.body.scrollTop+10;//
158.向下拉框指定位置添加项目
var op = document.createElement("OPTION");
document.all.selected_items.children(index).insertAdjacentElement("BeforeBegin",op);
op.text = document.all.all_items.text;
op.value = document.all.all_items.value;//
159.判断一个窗口是否已经打开，如果已经打开，则关闭之
var a;
if(a)
a.close();
else
a=window.open('','','');//
160.动态创建一个标签
newElem = document.createElement("DIV");
newElem.id = "hint_layer";
document.body.appendChild(newElem);
document.all.hint_layer.innerText="guoguo";//
161.标题栏
document.title//
162.背景图片
<body style="BACKGROUND-ATTACHMENT: fixed" background="img/bgfix.gif" ></body>//背景图片不动
<STYLE TYPE="text/css">
<!--
BODY {background-image:img/bgchild.jpg;
background-position: center;
background-repeat: no-repeat;
background-attachment: fixed;}
-->
</STYLE>//背景图片居中
163.设置透明效果
document.form.xxx.filters.alpha.opacity=0～100//
164.定义方法
var dragapproved=false;
document.onmouseup=new Function("dragapproved = false");//
165.将数字转化为人民币大写形式
function convertCurrency(currencyDigits) {
// Constants:
var MAXIMUM_NUMBER = 99999999999.99;
// Predefine the radix characters and currency symbols for output:
var CN_ZERO = "零";
var CN_ONE = "壹";
var CN_TWO = "贰";
var CN_THREE = "叁";
var CN_FOUR = "肆";
var CN_FIVE = "伍";
var CN_SIX = "陆";
var CN_SEVEN = "柒";
var CN_EIGHT = "捌";
var CN_NINE = "玖";
var CN_TEN = "拾";
var CN_HUNDRED = "佰";
var CN_THOUSAND = "仟";
var CN_TEN_THOUSAND = "万";
var CN_HUNDRED_MILLION = "亿";
var CN_SYMBOL = "人民币";
var CN_DOLLAR = "元";
var CN_TEN_CENT = "角";
var CN_CENT = "分";
var CN_INTEGER = "整";
// Variables:
var integral; // Represent integral part of digit number.
var decimal; // Represent decimal part of digit number.
var outputCharacters; // The output result.
var parts;
var digits, radices, bigRadices, decimals;
var zeroCount;
var i, p, d;
var quotient, modulus;
// Validate input string:
currencyDigits = currencyDigits.toString();
if (currencyDigits == "") {
alert("Empty input!");
return "";
}
if (currencyDigits.match(/[^,.\d]/) != null) {
alert("Invalid characters in the input string!");
return "";
}
if ((currencyDigits).match(/^((\d{1,3}(,\d{3})*(.((\d{3},)*\d{1,3}))?)|(\d+(.\d+)?))$/) == null) {
alert("Illegal format of digit number!");
return "";
}
// Normalize the format of input digits:
currencyDigits = currencyDigits.replace(/,/g, ""); // Remove comma delimiters.
currencyDigits = currencyDigits.replace(/^0+/, ""); // Trim zeros at the beginning.
// Assert the number is not greater than the maximum number.
if (Number(currencyDigits) > MAXIMUM_NUMBER) {
alert("Too large a number to convert!");
return "";
}
// Process the coversion from currency digits to characters:
// Separate integral and decimal parts before processing coversion:
parts = currencyDigits.split(".");
if (parts.length > 1) {
integral = parts[0];
decimal = parts[1];
// Cut down redundant decimal digits that are after the second.
decimal = decimal.substr(0, 2);
}
else {
integral = parts[0];
decimal = "";
}
// Prepare the characters corresponding to the digits:
digits = new Array(CN_ZERO, CN_ONE, CN_TWO, CN_THREE, CN_FOUR, CN_FIVE, CN_SIX, CN_SEVEN, CN_EIGHT,
CN_NINE);
radices = new Array("", CN_TEN, CN_HUNDRED, CN_THOUSAND);
bigRadices = new Array("", CN_TEN_THOUSAND, CN_HUNDRED_MILLION);
decimals = new Array(CN_TEN_CENT, CN_CENT);
// Start processing:
outputCharacters = "";
// Process integral part if it is larger than 0:
if (Number(integral) > 0) {
zeroCount = 0;
for (i = 0; i < integral.length; i++) {
p = integral.length - i - 1;
d = integral.substr(i, 1);
quotient = p / 4;
modulus = p % 4;
if (d == "0") {
zeroCount++;
}
else {
if (zeroCount > 0)
{
outputCharacters += digits[0];
}
zeroCount = 0;
outputCharacters += digits[Number(d)] + radices[modulus];
}
if (modulus == 0 && zeroCount < 4) {
outputCharacters += bigRadices[quotient];
}
}
outputCharacters += CN_DOLLAR;
}
// Process decimal part if there is:
if (decimal != "") {
for (i = 0; i < decimal.length; i++) {
d = decimal.substr(i, 1);
if (d != "0") {
outputCharacters += digits[Number(d)] + decimals;
}
}
}
// Confirm and return the final output string:
if (outputCharacters == "") {
outputCharacters = CN_ZERO + CN_DOLLAR;
}
if (decimal == "") {
outputCharacters += CN_INTEGER;
}
outputCharacters = CN_SYMBOL + outputCharacters;
return outputCharacters;
}//
166.xml数据岛绑定表格
<html>
<body>
<xml id="abc" src="test.xml"></xml>
<table datasrc='#abc'>
<thead>
<td>接收人</td>
<td>发送人</td>
<td>主题</td>
<td>内容</td>
</thead>
<tfoot>
<tr><th>表格的结束</th></tr>
</tfoot>
<tr>
<td><div datafld="to"></div></td>
<td><div datafld="from"></div></td>
<td><div datafld="subject"></div></td>
<td><div datafld="content"></div></td>
</tr>
</table>
</body>
</html>
//cd_catalog.xml
<?xml version="1.0" encoding="ISO-8859-1" ?>
<!-- Edited with XML Spy v4.2
-->
<CATALOG>
<CD>
<TITLE>Empire Burlesque</TITLE>
<ARTIST>Bob Dylan</ARTIST>
<COUNTRY>USA</COUNTRY>
<COMPANY>Columbia</COMPANY>
<PRICE>10.90</PRICE>
<YEAR>1985</YEAR>
</CD>
<CD>
<TITLE>Hide your heart</TITLE>
<ARTIST>Bonnie Tyler</ARTIST>
<COUNTRY>UK</COUNTRY>
<COMPANY>CBS Records</COMPANY>
<PRICE>9.90</PRICE>
<YEAR>1988</YEAR>
</CD>
<CD>
<TITLE>Greatest Hits</TITLE>
<ARTIST>Dolly Parton</ARTIST>
<COUNTRY>USA</COUNTRY>
<COMPANY>RCA</COMPANY>
<PRICE>9.90</PRICE>
<YEAR>1982</YEAR>
</CD>
<CD>
<TITLE>Still got the blues</TITLE>
<ARTIST>Gary Moore</ARTIST>
<COUNTRY>UK</COUNTRY>
<COMPANY>Virgin records</COMPANY>
<PRICE>10.20</PRICE>
<YEAR>1990</YEAR>
</CD>
</CATALOG>
//
167.以下组合可以正确显示汉字
================================
xml保存编码 xml页面指定编码
ANSI gbk/GBK、gb2312
Unicode unicode/Unicode
UTF-8 UTF-8
================================
168.XML操作
<xml id="xmldata" src="/data/books.xml">
<div id="guoguo"></div>
<script>
var x=xmldata.recordset //取得数据岛中的记录集
if(x.absoluteposition < x.recordcount) //如果当前的绝对位置在最后一条记录之前
{
x.movenext(); //向后移动
x.moveprevious(); //向前移动
x.absoluteposition=1; //移动到第一条记录
x.absoluteposition=x.recordcount;//移动到最后一条记录，注意记录集x.absoluteposition是从1到记录集记录的个
数的
guoguo.innerText=xmldso.recordset("field_name"); //从中取出某条记录
}
</script>
169.动态修改CSS的另一种方式
this.runtimeStyle.cssText = "color:#990000;border:1px solid #cccccc";//
170.正则表达式
匹配中文字符的正则表达式： [\u4e00-\u9fa5]
匹配双字节字符(包括汉字在内)：[^\x00-\xff]
应用：计算字符串的长度（一个双字节字符长度计2，ASCII字符计1）
String.prototype.len=function(){return this.replace([^\x00-\xff]/g,"aa").length;}
匹配空行的正则表达式：\n[\s| ]*\r
匹配HTML标记的正则表达式：/<(.*)>.*<\/\1>|<(.*) \/>/
匹配首尾空格的正则表达式：(^\s*)|(\s*$)
应用：javascript中没有像vbscript那样的trim函数，我们就可以利用这个表达式来实现，如下：
String.prototype.trim = function()
{
return this.replace(/(^\s*)|(\s*$)/g, "");
}
////////利用正则表达式分解和转换IP地址：
