如何使用密钥代码只允许将某些数字输入文本框？ [英] How do I allow only certain numbers to be entered into textbox using keycodes?

问题描述

 var specialKeys = new Array（）; 
 specialKeys.push（8）; // Backspace 
函数IsNumericss（e）{
 var keyCode = e.which？ e.which：e.keyCode 
 var ret =（（keyCode> = 49&& keyCode< = 57）|| specialKeys.indexOf（keyCode）！= -1）; 
返回ret; 
} 

这只允许1-9号码，但我还需要允许这段时间，或者键盘代码110& 190.

我该如何做到这一点？

我尝试过类似的东西，但无济于事：

 var ret =（（keycode> = 49&& keycode< = 57&& keycode == 110&& keycode == 190）

解决方案

< blockquote>这里有很好的解释： http://www.javascripter.net/faq/keyboardinputfiltering.htm [ ^ ]。



您需要添加额外的支票。

 ret =（ 49 < = keyCode&& keyCode< =  57 ）|| 
（ 110 < = keyCode&& keyCode< =  190 ）|| 
（ 8  == keyCode）; 

请注意，我还删除了多余的外部br ackets并排除了数组的使用，你只是用它来检查退格（8），这没什么意义。保持简单。

-SA

var specialKeys = new Array();
        specialKeys.push(8); //Backspace
        function IsNumericss(e) {
            var keyCode = e.which ? e.which : e.keyCode
            var ret = ((keyCode >= 49 && keyCode <= 57) || specialKeys.indexOf(keyCode) != -1);
            return ret;
        }

This allows numbers 1-9 only but I need to allow the period also or keycodes 110 & 190.
How would I go about doing this?
I tried something like this but to no avail:

var ret = ((keycode >= 49 && keycode <= 57 && keycode == 110 && keycode == 190)

解决方案

This is well explained here: http://www.javascripter.net/faq/keyboardinputfiltering.htm[^].

You need to add an additional check.

ret = (49 <= keyCode && keyCode <= 57) ||
      (110 <= keyCode && keyCode <= 190) ||
      (8 == keyCode);

Note that I also removed redundant outer brackets and excluded the use of the array, which you used just for the check for backspace (8), which makes little sense. Keep it simple.

—SA

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