可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试):

问题:

I want to display script errors in a popup alert instead of showing them in the browser console.

window.onerror = function() {
  var message = /* get error messages and put them here */;
  alert(message);
  return true;
};

回答1:

Yes, that is the correct way.

See the reference here:

http://www.javascriptkit.com/javatutors/error2.shtml

And explanation of how to see more details of the error here:

http://www.javascriptkit.com/javatutors/error3.shtml

Their example:

window.onerror = function(msg, url, linenumber) {
    alert('Error message: '+msg+'\nURL: '+url+'\nLine Number: '+linenumber);
    return true;
}

If you wish to display a LIST of errors in a single pop-up, it's trickier.

Since the errors occue 1 by 1, you need to do the following:

have window.onerror handler store error details in some array
Check that array periodically - either via a timer, or on every N'th call of window.onerror handler, or both.

When the check happens, process entire array, display contents as desired, and empty out an array

回答2:

Just in case someone would like to use it with jQuery:

$(window).on("error", function(evt) {

    console.log("jQuery error event:", evt);
    var e = evt.originalEvent; // get the javascript event
    console.log("original event:", e);
    if (e.message) { 
        alert("Error:\n\t" + e.message + "\nLine:\n\t" + e.lineno + "\nFile:\n\t" + e.filename);
    } else {
        alert("Error:\n\t" + e.type + "\nElement:\n\t" + (e.srcElement || e.target));
    }
});

回答3:

Have a look at The onerror event of the window object, specifically Getting additional details on an error

回答4:

Check this out: http://www.javascriptkit.com/javatutors/error3.shtml. Looks like signature is function(message, url, linenumber).

回答5:

Help to solve this issue

Character if exceeds in name 20 error message should be displayed dont use max in html here.
Date of birth should be between 1990-2010
All should be displayed in alert popup

<script>
function validation(){
   
    var errorMsg = new Array();

    if(!document.getElementById("name").value){
        errorMsg.push("Please Enter Full Name");
    }

    if(!document.getElementById("age").value){
        errorMsg.push("Please Enter age");
    }

   if(!document.getElementById("designation").value){
        errorMsg.push("Please Enter designation");
    }

    if(!document.getElementById("salary").value){
        errorMsg.push("Please Enter salary");
    }

  

    if(!document.getElementById("dob").value){
        errorMsg.push("Please Enter dob");
    }

    var messageHtml = "";

    errorMsg.forEach(function (message) {
        messageHtml += "<li>" + message + "</li>";
    }

    document.getElementById("error").innerHTML = messageHtml;
}
</script>

<style>
#empForm{

 position:absolute;
padding-left: 10px;
    top: 25%;
    left: 55%;
    width:18em;
    height:20em;
    margin-top: -9em; 
    margin-left: -15em; 
    border: 1px solid #ccc;
    background-color: #f3f3f3;
}
#salary{

    margin-left: 48px;
}
#date{
    margin-left: 6px;
padding-right: 26px;
}
#designation{
margin-left: 10px;
}
#age{
margin-left: 59px;
}
#name{
margin-left: 47px;
}
#submit{

}
</style>

<html>
<head>
<title>Employee Details</title>
<body>


<div id=empForm>
<h1>Registration Form</h1>

<form name="EmployeeData" action="return validation()">
<div><label>Name </label><input type="text" id="name" name="name"></div></br>

<div><label>Age </label><input type="number" id="age" name="age"></div></br>

<div><label>Designation </label><input type="text" id="designation" name="designation"></div></br>

<div><label>Salary </label><input type="number" id="salary" name="salary"></div></br>

<div><label>Date of Birth </label><input type="date" id="date" name="date"></div></br>

<div id="submit"><center><input type="submit" name="submit" ></center></div>
</div>
</body>
</html>

回答6:

<script>$(window).on("error", function(evt) {

console.log("jQuery error event:", evt);
var e = evt.originalEvent; // get the javascript event
console.log("original event:", e);
if (e.message) { 
    alert("Error:\n\t" + e.message + "\nLine:\n\t" + e.lineno + "\nFile:\n\t" + e.filename);
} else {
    alert("Error:\n\t" + e.type + "\nElement:\n\t" + (e.srcElement || e.target));
}
});
</script>