jsは数字、字母、中国語を判断します.

js    ，  ，   
1. 

var reg = /^(\w|[\u4E00-\u9FA5])*$/; 
if(arr=username.match(reg)) 
{ 
ti=1; 
return ture; 
} 
else 
{ 
alert("         ，        ,
                "); 
ti=0; 
return false; 
} 

2.                      ： 

              ：onkeyup="value=value.replace(/[^\u4E00-\u9FA5]/g,'')" onbeforepaste="clipboardData.setData('text',clipboardData.getData('text').replace(/[^\u4E00-\u9FA5]/g,''))" 

                ： onkeyup="value=value.replace(/[^\uFF00-\uFFFF]/g,'')" onbeforepaste="clipboardData.setData('text',clipboardData.getData('text').replace(/[^\uFF00-\uFFFF]/g,''))" 

              ：onkeyup="value=value.replace(/[^\d]/g,'') "onbeforepaste="clipboardData.setData('text',clipboardData.getData('text').replace(/[^\d]/g,''))" 

                 ：onkeyup="value=value.replace(/[\W]/g,'') "onbeforepaste="clipboardData.setData('text',clipboardData.getData('text').replace(/[^\d]/g,''))" 


   
<script> 
function check() 
{ 
if(!isNaN(document.all.form.str.value)) 
{ 
alert("  "); 
} 
</script> 
   
<script> 
function check() 
{ 
var str = /[_a-zA-Z]/; 
if(str.test(document.all.form.str.value)) 
{ 
alert("  "); 
} 
} 
</script> 
<form name="form" action="" onsubmit="return check();"> 
<input type=text name=str> 
<input type=submit> 
<form> 

--------------------------------------------------- 
/** 
*      javascript  (  ) 
* 
*      ，    String      
*      .js  ，               
* 
*         
* ----------- -------------------------------- 
* Trim        
* Occurs             
* isDigit           
* isAlpha                 
* isNumber        
* lenb       
* isInChinese          
* isEmail    email   
* isDate        ，         
* isInList               
* isInList               
*/ 

/***        ***/ 
String.prototype.Trim = function() { 
return this.replace(/(^\s*)|(\s*$)/g, ""); 
} 

/***             ***/ 
String.prototype.Occurs = function(ch) { 
// var re = eval("/[^"+ch+"]/g"); 
// return this.replace(re, "").length; 
return this.split(ch).length-1; 
} 

/***           ***/ 
String.prototype.isDigit = function() { 
var s = this.Trim(); 
return (s.replace(/\d/g, "").length == 0); 
} 

/***                 ***/ 
String.prototype.isAlpha = function() { 
return (this.replace(/\w/g, "").length == 0); 
} 
/***        ***/ 
String.prototype.isNumber = function() { 
var s = this.Trim(); 
return (s.search(/^[+-]?[0-9.]*$/) >= 0); 
} 

/***       ***/ 
String.prototype.lenb = function() { 
return this.replace(/[^\x00-\xff]/g,"**").length; 
} 

/***          ***/ 
String.prototype.isInChinese = function() { 
return (this.length != this.replace(/[^\x00-\xff]/g,"**").length); 
} 

/***    email   ***/ 
String.prototype.isEmail = function() { 
　var strr; 
var mail = this; 
　var re = /(\w+@\w+\.\w+)(\.{0,1}\w*)(\.{0,1}\w*)/i; 
　re.exec(mail); 
　if(RegExp.$3!="" && RegExp.$3!="." && RegExp.$2!=".") 
strr = RegExp.$1+RegExp.$2+RegExp.$3; 
　else 
　　if(RegExp.$2!="" && RegExp.$2!=".") 
strr = RegExp.$1+RegExp.$2; 
　　else 
　strr = RegExp.$1; 
　return (strr==mail); 
} 

/***        ，         ***/ 
String.prototype.isDate = function() { 
var p; 
var re1 = /(\d{4})[ ./-](\d{1,2})[ ./-](\d{1,2})[ ]?$/; 
var re2 = /(\d{1,2})[ ./-](\d{1,2})[ ./-](\d{2})[ ]?$/; 
var re3 = /(\d{1,2})[ ./-](\d{1,2})[ ./-](\d{4})[ ]?$/; 
if(re1.test(this)) { 
p = re1.exec(this); 
return new Date(p[1],p[2],p[3]); 
} 
if(re2.test(this)) { 
p = re2.exec(this); 
return new Date(p[3],p[1],p[2]); 
} 
if(re3.test(this)) { 
p = re3.exec(this); 
return new Date(p[3],p[1],p[2]); 
} 
return false; 
} 
/***               ***/ 
String.prototype.isInList = function(list) { 
var re = eval("/["+list+"]/"); 
return re.test(this); 
} 

/// <summary> 
///       
/// </summary> 
/// <returns>        ，   ，     </returns> 
String.prototype.IsDigit = function() 
{ 
    var reg = /^\d+$/g; 
    return reg.test(this); 
} 

/// <summary> 
///          
/// </summary> 
/// <returns>        ，   ，     </returns> 
String.prototype.IsAlphaDigit = function() 
{ 
    var reg = /^[a-zA-Z0-9]+$/g; 
    return reg.test(this); 
} 

/// <summary> 
///      、       
/// </summary> 
/// <returns>     、      ，   ，     </returns> 
String.prototype.IsAlpha = function() 
{ 
    var reg = /^\w+$/g; 
    return reg.test(this); 
}