阻止某些字符在文本框中键入? [英] Block some characters from being typed in a text box?

问题描述

我想阻止用户在文本框中键入某些字符(只允许[a-z]，[A-Z]和下划线).我从上一个问题中得到了答案，但是如果按箭头键(在FF 3.6中)，则会出现js错误:

I'd like to block users from typing certain characters in a text box (want to only allow [a-z], [A-Z], and underscore). I took this from a previous Q, but if I press the arrow keys (in FF 3.6), I get a js error:

"window.event is undefined"

这是原始代码，在这种情况下，我可以将window.event更改为什么?:

this is the original code, what can I change window.event to in this case?:

$("#myTextBox").bind("keypress", function(event) { 
    var charCode = (event.which) ? event.which : window.event.keyCode;  
    if (charCode <= 13) { 
        return true; 
    } 
    else { 
        var keyChar = String.fromCharCode(charCode); 
        var re = /[a-zA-Z_]/ 
        return re.test(keyChar); 
    }
});

谢谢

推荐答案

您可以执行以下操作:

$("#myTextBox").bind("keypress", function(event) { 
    var charCode = event.which;
    if (charCode <= 13) return true; 

    var keyChar = String.fromCharCode(charCode); 
    return /[a-zA-Z_]/.test(keyChar); 
});​

jQuery已将event.which标准化. .您可以在此处进行测试:)

如果没有，则解决方法将是event.keyCode，您想引用作为参数传递给此函数的event，而不是window的属性.在这种情况下，如果if条件为true，它将返回...因此不需要if/else，您可以像上面一样简化它.

If it didn't, the fix would just be event.keyCode, you want to refer to the event passed as the parameter to this function, not a property on window. In this case, if the if condition was true, it'd return...so there's no need for an if/else, you can simplify it like I have above.

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