JavaScript equivalent of PHP’s die

throw new Error("my error message");

You can only break a block scope if you label it. For example:

myBlock: {
  var a = 0;
  break myBlock;
  a = 1; // this is never run
};
a === 0;

You cannot break a block scope from within a function in the scope. This means you can't do stuff like:

foo: { // this doesn't work
  (function() {
    break foo;
  }());
}

You can do something similar though with functions:

function myFunction() {myFunction:{
  // you can now use break myFunction; instead of return;
}}

You can simply use the return; example 

$(document).ready(function () {
        alert(1);
        return;
        alert(2);
        alert(3);
        alert(4);
});

The return will return to the main caller function test1(); and continue from there to test3();

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" dir="ltr" lang="en">
<head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
</head>
<body>
<script type="text/javascript">
function test1(){
    test2();
    test3();
}

function test2(){
    alert(2);
    return;
    test4();
    test5();
}

function test3(){
    alert(3);
}

function test4(){
    alert(4);
}

function test5(){
    alert(5);
}
test1();

</script>
</body>
</html>

but if you just add throw ''; this will completely stop the execution without causing any errors.

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" dir="ltr" lang="en">
<head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
</head>
<body>
<script type="text/javascript">
function test1(){
    test2();
    test3();
}

function test2(){
    alert(2);
    throw '';   
    test4();
    test5();
}

function test3(){
    alert(3);
}

function test4(){
    alert(4);
}

function test5(){
    alert(5);
}
test1();

</script>
</body>
</html>

This is tested with firefox and chrome. I don't know how this is handled by IE or Safari

Tags:

Javascript

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