jquery keyup函数检查数字 [英] jquery keyup function check if number

问题描述

我尝试创建一个输入字段，用户只能在其中输入数字。这个函数已经为我工作了。

i am trying to create an input field where the user can only type in numbers. this function is already working almost fine for me:

        $('#p_first').keyup(function(event){
        if(isNaN(String.fromCharCode(event.which))){
            var value = $(this).val();

            $(this).val(value.substr(0,value.length-1));
        }
    });

但问题是，当用户握住带有字符的键时，功能键不触发。 ...任何想法如何我可以禁止这个？

but the problem is, whe the user holds the key with an character the function keyup is not triggering.... any ideas how i can forbid this?

推荐答案

尝试绑定到 keypress 事件，而不是 keyup 。当按下键时，它会反复触发。当按下的键不是数字时，您可以调用 preventDefault（），这将使键不被放在输入标签中。

Try binding to the keypress event instead of keyup. It gets fired repeatedly when a key is held down. When the key pressed is not a number you can call preventDefault() which will keep the key from being placed in the input tag.

   $('#p_first').keypress(function(event){

       if(event.which != 8 && isNaN(String.fromCharCode(event.which))){
           event.preventDefault(); //stop character from entering input
       }

   });

工作示例： http://jsfiddle.net/rTWrb/2/

Working Example: http://jsfiddle.net/rTWrb/2/

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