所以我找到了这个页面，并不是很喜欢我找到的解决方案，所以我想出了一个，并把它提供给你们所有人。对我来说，只有当我输入字母时，大写锁才重要。这段代码为我解决了问题。它快速和简单，给你一个辣椒变量引用，只要你需要它。

let capsIsOn=false; let capsChecked=false; let capsCheck=(e)=>{ let letter=e.key; if(letter.length===1 && letter.match(/[A-Za-z]/)){ if(letter!==letter.toLowerCase()){ capsIsOn=true; console.log('caps is on'); }else{ console.log('caps is off'); } capsChecked=true; window.removeEventListener("keyup",capsCheck); }else{ console.log("not a letter, not capsCheck was performed"); } } window.addEventListener("keyup",capsCheck); window.addEventListener("keyup",(e)=>{ if(capsChecked && e.keyCode===20){ capsIsOn=!capsIsOn; } });

We use getModifierState to check for caps lock, it's only a member of a mouse or keyboard event so we cannot use an onfocus. The most common two ways that the password field will gain focus is with a click in or a tab. We use onclick to check for a mouse click within the input, and we use onkeyup to detect a tab from the previous input field. If the password field is the only field on the page and is auto-focused then the event will not happen until the first key is released, which is ok but not ideal, you really want caps lock tool tips to display once the password field gains focus, but for most cases this solution works like a charm.

HTML

<input type="password" id="password" onclick="checkCapsLock(event)" onkeyup="checkCapsLock(event)" />

JS

function checkCapsLock(e) {
  if (e.getModifierState("CapsLock")) {
    console.log("Caps");
  }
}

https://codepen.io/anon/pen/KxJwjq

试着使用这段代码。

$('selectorOnTheInputTextBox').keypress(function (e) {
        var charCode = e.target.value.charCodeAt(e.target.value.length - 1)
        var capsOn = 
            e.keyCode && 
            !e.shiftKey &&
            !e.ctrlKey &&
            charCode >= 65 && 
            charCode <= 90;

            if (capsOn) 
               //action if true
            else
               //action if false
});

祝你好运!

最近在hashcode.com上有一个类似的问题，我创建了一个jQuery插件来处理它。它还支持对数字的大写锁定识别。(在标准德语键盘布局上，大写锁定对数字有影响)。

你可以在这里查看最新版本:jquery.capsChecker

Javascript代码

<script type="text/javascript">
   function isCapLockOn(e){
   kc = e.keyCode?e.keyCode:e.which;
   sk = e.shiftKey?e.shiftKey:((kc == 16)?true:false);
   if(((kc >= 65 && kc <= 90) && !sk)||((kc >= 97 && kc <= 122) && sk))
       document.getElementById('alert').style.visibility = 'visible';
   else
       document.getElementById('alert').style.visibility = 'hidden';
   }
</script>

现在我们需要使用Html来关联这个脚本

<input type="password" name="txtPassword" onkeypress="isCapLockOn(event)" />
<div id="alert" style="visibility:hidden">Caps Lock is on.</div> 

在jQuery中,

$('#example').keypress(function(e) { 
    var s = String.fromCharCode( e.which );
    if ( s.toUpperCase() === s && s.toLowerCase() !== s && !e.shiftKey ) {
        alert('caps is on');
    }
});

避免类似退格键的错误，需要s. tolowercase () !== s。