只允许在文本框中预定义charecter [英] allow only predefine charecter in textbox

问题描述

你好......

我有一个html文本框。我想通过javascript只允许文本框中的预定义字符。

Hello...
I have a html textbox. I want to allow only predefine charecter in textbox by javascript.

<input type="text" id="txt1"  onkeypress="allowChar(this, 'ABC123');" />

这是一个文本框示例。其中只允许资本A，资本B，资本C和数字仅1,2,3。

Here an example of textbox. In which allow only capital A, capital B, capital C and in numeric only 1,2,3.

<script type="text/javascript>
function allowChar(txt, char)
{
  ........
  ........
  ........
}
</script>

请按照您的意愿通过javascript或jquery解决这个问题。





谢谢

问候

Rakesh

Please solve this problem by javascript or jquery as you wish.


Thanks
Regards
Rakesh

推荐答案

您已经将Textbox对象和您的预定义字符传递给您的函数将那些字符与密钥代码匹配[ ^ ]试试这个：

HTML：

You are already passing Textbox Object and Your Predefined Chars to your function. Match the chars there with key codes[^]. Try this:
HTML:

<input type="text" id="txt1" class="customChar" önkeypress="return allowChar(this, 'ABC123');" />

JavaScript：

JavaScript:

function allowChar(textbox, chars){
    //check with key code here
    var keynum;
    if(window.event){ // IE					
    	keynum = e.keyCode;
    }else
        if(e.which){ // Netscape/Firefox/Opera					
    		keynum = e.which;
         }
    var EnteredWord = String.fromCharCode(keynum); //Here you got your pressed key    
    //If matching with the predefined characters stored in 'chars' then return true otherwise return false.
}

希望它有所帮助！

--Amit

Hope it helps!
--Amit

请参阅链接。它可能对你有所帮助。



防止对html文本字段输入特殊字符



event.preventDefault（）

Refer to the links. It may help you a bit.

Preventing special character input to html text field

event.preventDefault()

谷歌是你的朋友：好好经常拜访他。他可以比在这里发布问题更快地回答问题...



非常快速的搜索给出了200,000次点击：\"javascript限制文本框 [ ^ ]



将来，请尝试自己做至少基础研究，不要浪费你的时间或我们的时间。

Google is your friend: Be nice and visit him often. He can answer questions a lot more quickly than posting them here...

A very quick search gave 200,000 hits: "javascript restrict textbox"[^]

In future, please try to do at least basic research yourself, and not waste your time or ours.

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