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JavaScript

Nathan Marshall
Nathan Marshall
6,031 Points

Why won't my parameter be recognized anymore?

Hi Guys,

I am currently building my 'To Do List App' using only raw JavaScript. I am currently adding the functionality to not allow the user to add a string with an empty title from the input value.

I have managed to allow the user to not add anything if the value is equal to nothing. But now if I add something into the input area it doesn't allow me to add anything at all.

In the console, it says that my parameter isn't recognised any more? I have no idea why.

Could someone please explain what is going on? / How I should approach this?

Here is my CodePen: https://codepen.io/Nathan-Callum-Marshall/pen/qKJPRV?editors=0010

Thanks

1 Answer

Steven Parker
Steven Parker
230,248 Points

When the input is not empty, the code on lines 98-104 calls "createTaskItems" twice, and the first time it passes no argument. Since there's no error, "createTaskItems" attempts to attach new elements to the non-existent argument, causing the program to fail.

Replace that section of code to call "createTaskItems" only once, and always with a valid argument:

  if (createTaskItems(newTask) != "error") {
    contentArea.appendChild(newTask);
  }

Also, since you're using codepen, try using the "Tidy JS" function in the drop-down menu — particularly right before you publish. :wink:

Nathan Marshall
Nathan Marshall
6,031 Points

Yes that makes sense. Thanks for explaining that steve. You always seem to be the one solving my problems on here haha I appreciate it. I will also look up and Apply the Tidy.Js too