Passing dynamic parameter to a JavaScript function using innerHTML

Question

I am having issues passing a dynamic parameter to a JavaScript function using innerHTML.

Included below is the current code that I am using:

var name = "test";

frm.innerHtml = '<button name="close" id="close" title="Cancel" type="button"
     onclick="closeTab('+name+');">Return</button>';

When I debug the code of the closeTab() function, the parameter specified by the name variable is null .

I believe there is a problem with the declaration of the value while modifying the innerHTML property.

Any help would be greatly appreciated.

Thanks

Answer 1

Your resulting code is:

<button ... onclick="closeTab(test);">Return</button>

Can you see what's wrong? test is being treated as a variable, when you actually intended it to be a string.

I like to use JSON.stringify to make a variable parseable (kind of like var_export in PHP), but in this case you also need to escape quotes. So:

JSON.stringify(test).replace(/"/g,""")

Use that in your button instead of just test .

Answer 2

Your dynamic declaration is passing the parameter as a variable, instead of the value of the parameter. In order to correct this issue, you must pass the value as a string, instead of a variable, which is accomplished by encasing and escaping the variable in single quotes as demonstrated below:

var name = "test";

frm.innerHtml = '<button name="close"  id="close"  title="Cancel" type="button"
      onclick="closeTab(\''+name+'\');">Return</button>';

Answer 3

Using DOM:

var name="test";
var el = document.createElement("button");
el.name = "close";
el.id = "close";
el.title = "Cancel";
el.type = "button";
el.onclick = function() {  // an inline function that will be executed when el is clicked
    closeTab(name);        // `name` here contains `"test"`
};
frm.appendChild(el);

I really don't encourage overusing innerHTML as it is messy, and can sometime be slow.

Answer 4

Assuming your html is -

<form id='frm'>

</form>

Your JS should be -

var name = "test";
var innerHtml = "<button name='close' id='close' title='Cancel'   type='button'>Return</button>";
$("#frm").html(innerHtml);
$("#close").attr("onclick","javascript:closeTab('"+name+"');");

Check this out - http://jsfiddle.net/arindam006/avgHz/1/

This is the cleanest way to achieve this, though innerHtml is not a proper way to do it as everyone suggested above.

Answer 5

I simply used onclick="closeTab(name);"> in innerHTML and it worked. I guess that worked coz name is global variable.