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JavaScript编程笔记

新中……
1、数据类型验证问题
  Asp.Net虽然有验证控件,但是有些复杂的验证还是得传到服务器上进行,用js速度和性能都比较好
<script>
 //检查是否为任意数(实数)
function isNumeric(strNumber) {
var newPar=/^(-|\+)?\d+(\.\d+)?$/
alert(newPar.test(strNumber)); }
 //检查是否为正数
function isUnsignedNumeric(strNumber) {
var newPar=/^\d+(\.\d+)?$/
alert(newPar.test(strNumber)); }
//检查是否为整数
function isInteger(strInteger) {
var newPar=/^(-|\+)?\d+$/
alert(newPar.test(strInteger)); }
//检查是否为正整数
function isUnsignedInteger(strInteger) {
var newPar=/^\d+$/
alert(newPar.test(strInteger)); }
</script>
2、asp.net中用alert()实现换行问题
     asp.net中用response.Write("<script>alert('提示:\n操作出错!');</script>");无法执行。
     将字符串写成
     say="提示:\\n操作出错!"
     say=@"提示:\n操作出错!"
  
 3、js实现刷新验证码
     单击图片刷新:
<img id="CheckImg" src="CreatImage.aspx" onclick="this.src='CreatImage.aspx?temp='+Math.random()"/>
     单击“刷新验证码”按钮刷新
    function imagechick()
   {
     form1.CheckImg.src="CreatImage.aspx?temp="+Math.random();
     return false;//不上传到服务器
   }
     其中CreatImage.aspx为产生验证码图片的页面,源码见:C#产生图形验证码
4、js中使用正则表达式的方法
    格式是:/正则表达式/
    必须用两个斜杠把正则表达式括起来。
   如非法字符检测正则表达式为:^(?:[\u4e00-\u9fa5]*\w*\s*)+$
   使用的代码为:
      var newPar=/^(?:[\u4e00-\u9fa5]*\w*\s*)+$/;
      if(newPar.test("1234&1238*_~"))
      {
         &


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