Put code directly in popup window function

Question

For example, I have this script

<button onclick="myFunction()">Try it</button>
<script>
function myFunction() {
var myWindow = window.open("", "myWindow", "width=200,height=100");
myWindow.document.write("<p>This is 'myWindow'</p>");
myWindow.opener.document.write("<p>This is the source window!</p>");
}
</script>

Instead of

 myWindow.document.write("<p>This is 'myWindow'</p>");

I would want to put something like

 myWindow.document.write("<script> alert("h");</script>");

Due to circumstances, I cannot link to another page with the code in it. Putting the script makes the window not even open. Thanks

• Adrian: Just do "<script> alert('h');</script>"? Your problem is that you need to escape h or use a different set of quotation marks.
• treyBake: Possible duplicate of How to put "</script>" in a javascript string?
• user3125845: The problem is neither work.
• mplungjan: This question was caused by a problem that can no longer be reproduced or a simple typographical error. While similar questions may be on-topic here, this one was resolved in a manner unlikely to help future readers.
• mplungjan: You need myWindow.opener.document.close() at the end AND escape the / <\/script>

Answer 1

1. quotes
2. close the document (myWindow.document.close())
3. escape the </script> you cannot have </script> inside script tags.
4. NEVER document.write into an already rendered page

Something like this

function myFunction() {
 var myWindow = window.open("", "myWindow", "width=200,height=100");
 myWindow.document.write("<p>This is 'myWindow'</p>");
 myWindow.document.close();
 var p = document.createElement("p")
 p.innerHTML = "This is the source window!";
 myWindow.opener.document.querySelector("body").appendChild(p); // same as document.querySelector("body") 
}

If you want to use script, you need to

var myWindow = window.open("", "myWindow", "width=200,height=100");
myWindow.document.write("<script>alert('h')<\/script>"); // MANDATORY ESCAPE \/SCRIPT
myWindow.document.close();

• user3125845: Sorry but this doesn't really answer my question. The code works fine with text but once i put a script into it, it breaks. How would you put a script in the opened window?
• mplungjan: Your use case is unclear. What do you need to have in the child window and what in the parent window?
• user3125845: Look at my question. I want to put a script in the popup window.
• mplungjan: Look at my answer. You need to escape the end /script tag
• user3125845: OK I see it now. If i put a full webpage in there do I have to end all tags like that? Right now instead of the button it just says [Object Object]

Answer 2

Instead of double quotes wrap your content into single quote

myWindow.document.write('<script> alert("h");</script>');

• user3125845: Doesn't work, just writes it in plaintext next to the button.
• front_end_dev: Try to add this method reload script Working example - (function (){ var w = window.open(); w.document.write('<script> alert("h");</script>'); })();
• user3125845: Sorry, I don't really understand your code. What does it mean/do/ how do I use it?
• mplungjan: You cannot have </script> inside script tags.
• front_end_dev: @mplungjan Where did you find that in myWindow.document.write('<script> alert("h");</script>');