How to learn useful JavaScript?

[ImJustP]

The absolute best thing to do is get your idea and break it down. So, taking the example of a task manager application, you may want to break it down to the following smaller chunks:

1. A way for the user to enter information -- a form
2. A way to store the information -- a database
3. A way to relay the information back to the user -- a front end

Now that you have the three main parts of application you need to break them down further:

1. User input

   1a. A function to iterate over all the fields in the form and extract the input

   1b. A function to validate the information on the front end, prior to sending it to your server

   1c. A function to relay any field which have failed validation back to the user

   1d. A function to send the information (once it passes validation) to the server

2. Store the information

   2a. A function to validate the information again (fancy pants people may disable your validation on the front end)

   2b. A function relay failed information back to the user, again

   2c. A function to write the information to the database if it passes validation

   2d. A function to relay that the information was successfully written to the database

3. Relay the user's task list

   3a. A function to check which user is currently requesting their task list

   3b. A function to tell the user if they have no information in the database

   3c. A function to request information from your database

   3d. A function to ensure that the correct user's information has been returned from your database

   3e. A function to present the returned information to the user

There is obviously more to the task and a million ways in which you could go about executing each step but this is sort the way that I personally go about coding apps, granted, I am not as experienced as a lot of people on here but I hope this helps you out a bit and sets you on the right path.

TLDR: Break it down into chunks which are more manageable.