function check_email ( email )
{
var len = email.length;
if(len==0)
return "E-mail不能為空白!\n";
for(var i=0;i<len;i++)
{ var c= email.charAt(i);
if(!((c>="A"&&c<="Z")||(c>="a"&&c<="z")||(c>="0"&&c<="9")||(c=="-")||(c=="_")||(c==".")||(c=="@")))
return "E-mail格式不符!\n";
}
if((email.indexOf("@")==-1)||(email.indexOf("@")==0)||(email.indexOf("@")==(len-1)))
return "E-mail格式不符!\n";
if((email.indexOf("@")!=-1)&&(email.substring(email.indexOf("@")+1,len).indexOf("@")!=-1))
return "E-mail格式不符!\n";
if((email.indexOf(".")==-1)||(email.indexOf(".")==0)||(email.lastIndexOf(".")==(len-1)))
return "E-mail格式不符!\n";
return "";
}

function check_null ( column, name )
{
if( column.length == 0 )
return name + " 不能為空白 !\n";
return "";
}

function check_select ( select, name )
{
if( select.options[0].selected == true )
return name + " 需要有值 !\n";
return "";
}

function check_radio ( radio, name )
{
var error = true;
for( i=0; i <radio.length; i++ )
if( radio[i].checked == true ) {
error = false;
break;
}
if( error == true )
return name + "需要有值 !\n";
return "";
}

function check_checkbox ( check, name )
{
var error = true;
if( check.checked == true ) {
error = false;
}
if( error == true ){
return name + "需要選取 !\n";
}
return "";
}