Javascript函数只能在按键上输入字母 [英] Javascript Function to enter only alphabets on keypress
问题描述
我只想在< textarea> 中输入字符值，而另一个中输入数值。我已经能够创建一个JavaScript函数，它只允许使用 onkeypress < textarea> 中输入数值>。这适用于Firefox和Chrome。
对于字母表，我使用 windows.event 属性创建另一个JavaScript函数。只有问题是这只适用于Chrome而不适用于Firefox。
我想知道如何只允许使用 onkeypress输入字母
function isNumberKey（evt）{<！ - 仅接受函数数值 - > // var e = evt || window.event; var charCode =（evt.which）？ evt.which：evt.keyCode if（charCode！= 46&& charCode> 31&&（charCode< 48 || charCode> 57））return false;返回true; }函数ValidateAlpha（evt）{var keyCode =（evt.which）？ （（keyCode< 65 || keyCode> 90）&& amp;（keyCode< 97 || keyCode> 123）&& keyCode！= 32）返回false;返回true; }
< label for =cnameclass =标签>风险群集名称< / label>< textarea id =cnamerows =1pxcols =20pxstyle =resize：noneplaceholder =Cluster NameonKeyPress =return ValidateAlpha ）;>< / textarea>< br>< label for =cnum>风险丛集编号：< / label>< textarea id =cmunrows =1pxcols =12px style =resize：noneplaceholder =Cluster Numberonkeypress =return isNumberKey（event）>< / textarea>
如果你不需要支持旧版本的浏览器，我可以使用 input
code>事件。这样，如果用户将文本粘贴到 textarea 中，您还可以捕获非字母字符。
你的HTML一点点。最重要的变化是 cname 和 cnum 上的事件。请注意，两种情况下的事件都已更改为 oninput 。
< label for =cnameclass =label>风险群集名称< / label>
< label for =cnum>风险集群编号：< / label>
假设您希望 cname 只接受字符在字母表和 cnum 中只接受数字，您的JavaScript应该是：
function validateAlpha（）{
var textInput = document.getElementById（cname）。value;
textInput = textInput.replace（/ [^ A-Za-z] / g，）;
document.getElementById（cname）。value = textInput;
}
函数isNumberKey（）{
var textInput = document.getElementById（cmun）.value;
textInput = textInput.replace（/ [^ 0-9] / g，）;
document.getElementById（cmun）。value = textInput;
}
此代码使用正则表达式，这是匹配字符串中的模式的一种方式。
I want to enter only character values inside a <textarea> and numeric values in another. I have been able to make a JavaScript function which only allows numeric values to be entered in the <textarea> using onkeypress. This works in Firefox and Chrome.
For alphabets I am creating another JavaScript function using windows.event property. Only problem is this works only in Chrome and not in Firefox.
I want to know how to allow only alphabets to be entered using onkeypress event as used for entering only numeric values?
function isNumberKey(evt){ <!--Function to accept only numeric values-->
//var e = evt || window.event;
var charCode = (evt.which) ? evt.which : evt.keyCode
if (charCode != 46 && charCode > 31
&& (charCode < 48 || charCode > 57))
return false;
return true;
}
function ValidateAlpha(evt)
{
var keyCode = (evt.which) ? evt.which : evt.keyCode
if ((keyCode < 65 || keyCode > 90) && (keyCode < 97 || keyCode > 123) && keyCode != 32)
return false;
return true;
}
<label for="cname" class="label">The Risk Cluster Name</label>
<textarea id="cname" rows="1px" cols="20px" style="resize:none" placeholder="Cluster Name" onKeyPress="return ValidateAlpha(event);"></textarea>
<br>
<label for="cnum">Risk Cluster Number:</label>
<textarea id="cmun" rows="1px" cols="12px" style="resize:none" placeholder="Cluster Number" onkeypress="return isNumberKey(event)"></textarea>
If you don't need to support older browsers I would use the input event. This way you can also catch non-alpha characters if the user pastes text into the textarea.
I cleaned up your HTML a little bit. The most important changes are to the events on cname and cnum. Note that the event in both cases has been changed to oninput.
<label for="cname" class="label"> The Risk Cluster Name</label>
<textarea id="cname" rows="1" cols="20" style="resize:none" placeholder="Cluster Name" oninput="validateAlpha();"></textarea>
<label for="cnum">Risk Cluster Number:</label>
<textarea id="cmun" rows="1" cols="12" style="resize:none" placeholder="Cluster Number" oninput="isNumberKey();"></textarea><br /><br /><br />
Assuming you want cname to only accept characters in the alphabet and cnum to only accept numbers, your JavaScript should be:
function validateAlpha(){
var textInput = document.getElementById("cname").value;
textInput = textInput.replace(/[^A-Za-z]/g, "");
document.getElementById("cname").value = textInput;
}
function isNumberKey(){
var textInput = document.getElementById("cmun").value;
textInput = textInput.replace(/[^0-9]/g, "");
document.getElementById("cmun").value = textInput;
}
This code uses regular expressions, a way to match patterns in strings.
这篇关于Javascript函数只能在按键上输入字母的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
