限制Input只能输入数字

$("input[name='mobileNo']").keydown(function (event) {   
    if ($.browser.msie) {   
        if ( ((event.keyCode > 47) && (event.keyCode < 58)) ||   
              (event.keyCode == 8) ) {   
            return true;   
        } else {   
            return false;   
        }   
    } else {   
        if ( ((e.which > 47) && (e.which < 58)) ||   
              (e.which == 8) ) {   
            return true;   
        } else {   
            return false;   
        }   
    }   
}); 

 发现小键盘不能起作用,去网上查了下

  onkeypress() 事件
  keycode是一样的 但不能防止粘贴
  keydown和keyup的 keycode和小键盘是不一样的，并且效果对复制粘贴也是有效的

最后的版本：

可能版本不一样还是什么，我这里不需要判断浏览器类型,同样支持FF和ie

		$("input[name='test']").keydown(function (event) {  
        if ( ((event.keyCode > 47) && (event.keyCode < 58)) ||   
              (event.keyCode == 8)|| ((event.keyCode > 95) && (event.keyCode < 106)) ) {   
            return true;   
        } else {   
            return false;   
        }   
 
});   

 上面的支持IE,FF，Google不支持oprea

最后附上一些keycode

<script   type= "text/javascript "> 
function   showKeyName(e) 
{ 
var   keyName; 
switch(e.keyCode) 
{ 
case   8:keyName   =   e.keyCode+ "[退格] ";break; 
case   9:keyName   =   e.keyCode+ "[Tab] ";break; 
case   13:keyName   =   e.keyCode+ "[Enter] ";break; 
case   16:keyName   =   e.keyCode+ "[Shift] ";break; 
case   17:keyName   =   e.keyCode+ "[Ctrl] ";break; 
case   18:keyName   =   e.keyCode+ "[Alt] ";break; 
case   19:keyName   =   e.keyCode+ "[PauseBreak] ";break; 
case   20:keyName   =   e.keyCode+ "[Caps   Lock] ";break; 
case   27:keyName   =   e.keyCode+ "[Esc] ";break; 
case   32:keyName   =   e.keyCode+ "[空格] ";break; 
case   33:keyName   =   e.keyCode+ "[PageUp] ";break; 
case   34:keyName   =   e.keyCode+ "[PageDown] ";break; 
case   35:keyName   =   e.keyCode+ "[End] ";break; 
case   36:keyName   =   e.keyCode+ "[Home] ";break; 
case   37:keyName   =   e.keyCode+ "[方向键左] ";break; 
case   38:keyName   =   e.keyCode+ "[方向键上] ";break; 
case   39:keyName   =   e.keyCode+ "[方向键右] ";break; 
case   40:keyName   =   e.keyCode+ "[方向键下] ";break; 
case   45:keyName   =   e.keyCode+ "[Insert] ";break; 
case   46:keyName   =   e.keyCode+ "[Delete] ";break; 
case   91:keyName   =   e.keyCode+ "[左Win] ";break; 
case   92:keyName   =   e.keyCode+ "[右Win] ";break; 
case   93:keyName   =   e.keyCode+ "[快捷菜单键] ";break; 
case   95:keyName   =   e.keyCode+ "[Sleep] ";break; 
case   96:keyName   =   e.keyCode+ "[小键盘区0] ";break; 
case   97:keyName   =   e.keyCode+ "[小键盘区1] ";break; 
case   98:keyName   =   e.keyCode+ "[小键盘区2] ";break; 
case   99:keyName   =   e.keyCode+ "[小键盘区3] ";break; 
case   100:keyName   =   e.keyCode+ "[小键盘区4] ";break; 
case   101:keyName   =   e.keyCode+ "[小键盘区5] ";break; 
case   102:keyName   =   e.keyCode+ "[小键盘区6] ";break; 
case   103:keyName   =   e.keyCode+ "[小键盘区7] ";break; 
case   104:keyName   =   e.keyCode+ "[小键盘区8] ";break; 
case   105:keyName   =   e.keyCode+ "[小键盘区9] ";break; 
case   106:keyName   =   e.keyCode+ "[*] ";break; 
case   107:keyName   =   e.keyCode+ "[+] ";break; 
case   109:keyName   =   e.keyCode+ "[-] ";break; 
case   110:keyName   =   e.keyCode+ "[.] ";break; 
case   111:keyName   =   e.keyCode+ "[/] ";break; 
case   112:keyName   =   e.keyCode+ "[F1] ";break; 
case   113:keyName   =   e.keyCode+ "[F2] ";break; 
case   114:keyName   =   e.keyCode+ "[F3] ";break; 
case   115:keyName   =   e.keyCode+ "[F4] ";break; 
case   116:keyName   =   e.keyCode+ "[F5] ";break; 
case   117:keyName   =   e.keyCode+ "[F6] ";break; 
case   118:keyName   =   e.keyCode+ "[F7] ";break; 
case   119:keyName   =   e.keyCode+ "[F8] ";break; 
case   120:keyName   =   e.keyCode+ "[F9] ";break; 
case   121:keyName   =   e.keyCode+ "[F10] ";break; 
case   122:keyName   =   e.keyCode+ "[F11] ";break; 
case   123:keyName   =   e.keyCode+ "[F12] ";break; 
case   144:keyName   =   e.keyCode+ "[NumLock] ";break; 
case   145:keyName   =   e.keyCode+ "[ScrollLock] ";break; 
case   186:keyName   =   e.keyCode+ "[;] ";break; 
case   187:keyName   =   e.keyCode+ "[=] ";break; 
case   188:keyName   =   e.keyCode+ "[,] ";break; 
case   189:keyName   =   e.keyCode+ "[-] ";break; 
case   190:keyName   =   e.keyCode+ "[.] ";break; 
case   191:keyName   =   e.keyCode+ "[/] ";break; 
case   192:keyName   =   e.keyCode+ "[`] ";break; 
case   219:keyName   =   e.keyCode+ "[[] ";break; 
case   220:keyName   =   e.keyCode+ "[\\] ";break; 
case   221:keyName   =   e.keyCode+ "[]] ";break; 
case   222:keyName   =   e.keyCode+ "[ '] ";break; 
//case   255:keyName   =   e.keyCode+ "[Power] ";break; 
case   255:keyName   =   e.keyCode+ "[Wake] ";break; 
default:keyName   =   e.keyCode+ "[ "   +   String.fromCharCode(e.keyCode)   +   "] ";break; 
} 
if((e.shiftKey)&&(e.keyCode!=16)){keyName   =   e.keyCode+ "[Shift]   +   "   +   keyName;} 
if((e.altKey)&&(e.keyCode!=18)){keyName   =   e.keyCode+ "[Alt]   +   "   +   keyName;} 
if((e.ctrlKey)&&(e.keyCode!=17)){keyName   =   e.keyCode+ "[Ctrl]   +   "   +   keyName;} 
return   keyName; 
} 
</script>