无法将隐藏的表单值获取到javascript变量中

Question

I have a form with several fields. The value of one of the hidden fields is passed in the URL along with some other input values like this:

example.html#firstname=Homer&lastname=Simpson&itype=TARGET

I have a javascript that parses the URL and that is populating the form just fine. The output of the form contains all of the values passed from the url, so I know the variable are getting passed to the form fields.

My issue is - I want to be able to setup an if statement to change the text of one of the headings based on the value of itype.

Here's my code:

        var itypestuff = document.getElementById("itype").value;

        document.write ("<p>The value of the variable is " + itypestuff.value + "</p>");

        if( itypestuff == "TARGET" ){
           document.write("This is the target");
        }

        else{
           document.write("This is not the target");
        }

I added the first document.write statement as a debug and it's coming back with: The value of the variable is undefined

Here's what the itype field variable looks like:

    <input type="hidden" name="itype" id="itype" value="">

Any ideas how I can get the variable from the URL into my javascript variable so I can do my if statement?

Answer 1

Change :

 document.write ("<p>The value of the variable is " + itypestuff.value + "</p>");

To

document.write ("<p>The value of the variable is " + itypestuff + "</p>");

OR

Change

var itypestuff = document.getElementById("itype").value;

To

var itypestuff = document.getElementById("itype");
// And 
if( itypestuff.value == "TARGET" ){ //...

EDIT

You have to change your html like that :

<input type="hidden" name="itype" id="itype" value="<?= htmlspecialchars($_GET['itype']); ?>">

And call : example.php?firstname=Homer&lastname=Simpson&itype=TARGET