//判断是否为数字的函数
function isNumber( str )
{
	var num = JTrim( str );
	if ( num == "" || isNaN(num))
	{
		return (false);
	}
	if(parseInt(num,10)<0)
	{
		return false;
	}
	return (true);
}

//去空格的函数
function JTrim( str )
{
	return Jtrim( str );
}

function Jtrim(str)    
{
   
	var i = 0;
	var len = str.length;
	if ( str == "" ) return( str );
	j = len -1;
	flagbegin = true;    
	flagend = true;    
	while ( flagbegin == true && i< len) 
	{
	   if ( str.charAt(i) == " " ) 
		{
		  i=i+1;
		  flagbegin=true;
		}
		else
		{
			flagbegin=false;
		}
	} 
	       
	while  (flagend== true && j>=0)
	{
	    if (str.charAt(j)==" ")
		{ 
			j=j-1;
			flagend=true;
		}
		else
		{
			flagend=false;
		}
	}
	
	if ( i > j ) return ("")
	
	trimstr = str.substring(i,j+1);
	return trimstr;
}

function isValidYear( str )
{
	var year;
	year = str.parseInt( str, 10);
	if ( year == NaN ) {
		alert( "年份输入有误" );
		return (false);
	}
	if ( year>2003 || year < 2000 ) {
		alert( "年份在2000-2003之间" );
		return (false);
	}
	retrun (true);
}

function isValidMonth( str )
{
	var month;
	month = str.parseInt( str,10 );
	if ( month == NaN ) {
		alert( "月份输入有误" );
		return (false);
	}
	if ( month>12 || month < 1 ) {
		alert( "月份在01 - 12之间" );
		return (false);
	}
	retrun (true);
}

function isValidDay( str )
{
	var day;
	day = str.parseInt( str,10 );
	if ( day == NaN ) {
		alert( "日期输入有误" );
		return (false);
	}
	if ( day>31 || day < 1 ) {
		alert( "日期在01 - 31之间" );
		return (false);
	}
	retrun (true);
}

function isValidDate( str )
{
	var pos, pos2;
	var year, month, day;
	pos = str.indexOf("-");
	if (pos == -1) {
		alert("日期格式不对。正确的日期格式为YYYY-MM-DD，例如：2000-05-01");
		return (false);
	}
	pos2 = str.indexOf("-", pos +1);
	if (pos2 == -1) {
		alert("日期格式不对。正确的日期格式为YYYY-MM-DD，例如：2000-05-01");
		return (false);
	}

	year = str.substring(0, pos);
	month = str.substring( pos+1, pos2);
	day = str.substring( pos2+1, str.length);
	
	if ( year=="" || month==""|| day=="" ) {
		alert( "日期输入有误" );
		return (false);
	}

	if ( isNaN(year) || isNaN(month)|| isNaN(day) ) {
		alert( "日期输入有误" );
		return (false);
	}
	else {
		year = parseInt(year,10);
		month = parseInt(month,10);
		day = parseInt(day,10);
	}
	if ( year<1900 || year > 2003 ) {
		alert( "年份在2000-2003之间" );
		return (false);
	}
	if ( month < 1 || month > 12 ) {
		alert( "月份在01 - 12之间" );
		return (false);
	}
	if ( month==4 || month==6 || month==9 || month==11 ) {
		if ( day < 1 || day > 30 ) {
			alert( "日期在01 - 30之间" );
			return (false);
		}
	}
	else {
		if ( month!=2 ) {
			if ( day < 1 || day > 31 ) {
				alert( "日期在01 - 31之间" );
				return (false);
			}
		}
		else {	// month == 2
			if ( year==2000 || year==2004 ) {
				if ( day < 1 || day > 29 ) {
					alert( "日期在01 - 29之间" );
					return (false);
				}
			}
			else {
				if ( day < 1 || day > 28 ) {
					alert( "日期在01 - 28之间" );
					return (false);
				}
			}
		}
	}
	return (true);
}


//判断字符串长度
function strLen(str)
{
	var Chinese_OS;
	var strTest, ch, slen, i;
	Chinese_OS = false;
	strTest = "中文";
	if ( strTest.length == 2 )	Chinese_OS = true;
	if ( Chinese_OS ) {
		slen = 0;
		for ( i=0; i< str.length; i++){
			ch = str.charCodeAt( i );
			if ( ch<0 ) ch = ch + 65536;
			if ( ch>255 ) slen = slen +1;
			slen = slen +1;
		}
	}
	else
	{
		slen = str.length
	}
	return (slen);
}

//判断是否有中文字符
function hasChn(str)
{
	var ch, i;
	for ( i=0; i< str.length; i++){
		ch = str.charCodeAt( i );
		if ( ch<0 ) ch = ch + 65536;
		if ( ch>255 ) return(true);
	}
	return (false);
}


function isEmpty(s)
{  
	return ((s == null) || (s.length == 0))
}

function isWhitespace (s)
{  
  var whitespace = " \t\n\r";
  var i;
   for (i = 0; i < s.length; i++)
   {   
       var c = s.charAt(i);
       if (whitespace.indexOf(c) >= 0) 
	   {
		  return false;
	   }
   }
   return true;
}

function isVaildEmail(s)
{
//	if (!isWhitespace(s))
//	{
//		window.alert("输入的E-mail地址中不能包含空格符，请重新输入！");	
//		return false;
//	}

   // there must be >= 1 character before @, so we
   // start looking at character position 1
   // (i.e. second character)
   var i = 1;
   var len = s.length;

	if (len > 80)
	{
		window.alert("email地址长度不能超过80位!");
		return false;
	}
	
	pos1 = s.indexOf("@");
	pos2 = s.indexOf(".");
	pos3 = s.lastIndexOf("@");
	pos4 = s.lastIndexOf(".");
	//check '@' and '.' is not first or last character
	if ((pos1 <= 0)||(pos1 == len)||(pos2 <= 0)||(pos2 == len))  
	{
		window.alert("请输入有效的E-mail地址！");
		return false;
	}
	else
	{
		//check @. or .@
		if( (pos1 == pos2 - 1) || (pos1 == pos2 + 1) 
		  || ( pos1 != pos3 )  //find two @
		  || ( pos4 < pos3 ) ) //. should behind the '@'  		
		{
			window.alert("请输入有效的E-mail地址！");
			return false;
		}
	}

	return true;
}
function isEmail (s)
{
   	// is s Empty?
    if (isEmpty(s))
	{
		window.alert("输入的E-mail地址不能为空，请输入！");	
		return false;
	}
	//is s contain whitespace
    if(isVaildEmail(s))
		return true;
}


//判断表单项目是否符合要求的函数

function chsubmit(obj,checkclass,checkmessage)
{
	var reg;
	var checkstr;
	checkstr=true;
	switch(checkclass)
	{
		case "txt":
			if (JTrim(obj.value)==""){
				alert(checkmessage);
				obj.focus();
				checkstr=false;
		}
			
			break;
		case "num":
			reg = /^\d+(\.\d+)?$/;
			if (!reg.test(obj.value)){
				alert(checkmessage);
				obj.value="";
				obj.focus();
				checkstr=false;
			}
			break;
		case "date":
			reg = /^(19|20)\d\d\-(0|1)?\d\-(0|1|2|3)?\d$/;
			if (!reg.test(obj.value)){
				alert(checkmessage);
				obj.value="";
				obj.focus();
				checkstr=false;
			}
			break;
		case "email":
			reg = /^\w+([-+.]\w+)*@\w+([-.]\\w+)*\.\w+([-.]\w+)*$/;
			if (!reg.test(obj.value)){
				alert(checkmessage);
				obj.value="";
				obj.focus();
				checkstr=false;
			}
			break;
		case "script":
			reg =/<\/?script[^>]*>/
			if (!reg.test(obj.value)){
				alert(checkmessage);
				obj.value="";
				obj.focus();
				checkstr=false;
			}
			break;
		
	}
	return checkstr;
}


//检查表单项目是否存在的函数

	function checkobj(objform,objstr)
	{
		var tmp
		tmp=false
		for(i=0;i<objform.length;i++)
		{
			if(objform.elements[i].name==objstr)
				{
					tmp=true;
					}
			}
		return tmp
		}

//表单项目长度的函数,如果表单里就一个该项目时返回

	function objlength(objform,objstr)
	{
		var tmpi=0
		
		for(i=0;i<objform.length;i++)
		{
			if(objform.elements[i].name==objstr)
				{
					tmpi++;
					}
			}
		return tmpi
		}
		
		
//删除下拉列表框中的值
		
function DelSelect(psSelName)
{
   var oSelect = document.getElementById(psSelName)
   
   var iCount;
   for (iCount = oSelect.length ; iCount >= 0; iCount--)
   {
      oSelect.options[iCount] = null;      
   }   
}


//增加下拉列表框中的值
function AddSelect(psSelName, psId, psName)
{	
	var oSelect = document.getElementById(psSelName)
  
   oSelect.options[oSelect.length] = new Option(psName, psId);
}