js:
function onlyNumber(event){
var keyCode = event.keyCode;
if((keyCode<48&&keyCode>8) ||(keyCode>57&&keyCode<96) ||keyCode<8||keyCode>105){//8为删除键96到106为小键盘
window.event.returnValue= false;
}
}
$(function(){
$("#numberbox").keydown(onlyNumber);
});html:
<input type="text" id="numberbox"/>