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JavaScript

Substring Function in JS

Hello everyone! How would I create my own substring function for a challenge? I came off on this challenge asking me to create my own substring! I've researched and tried on my own but haven't figured it out? Can anyone please help me! Thank You

Steven Parker
Steven Parker
229,582 Points

I'm not quite clear on what the objective is. Can you provide a link to the page you are referring to?

The objective is how do you create YOUR OWN substring function

Steven Parker
Steven Parker
229,582 Points

Sure, but I'm not clear on what a "substring function" would do. I'm expecting the page you saw this on would be likely to provide those details. Can you post a link to it here?

1 Answer

Steven Parker
Steven Parker
229,582 Points

Without seeing the actual instructions, I'm going to guess that what you want to do is to re-create the functionality of the built-in "substr" string method. So, start with the functional definition (obtained from MDN):

str.substr(start[, length]) extracts length characters from a string, counting from the start index.

You might begin with a loop that goes from the "start" value and runs for "length" characters, or until the end, whichever is shorter.

Inside your loop, you might take the character from the current index position and add it to a new string being created.

When the loop ends you could return the newly-created string.

So if I have the right idea, that should help you get started.

can you please give me an example of what you just explained

Steven Parker
Steven Parker
229,582 Points

There are plenty examples of loops, indexing, and using string properties throughout the courses. I'm only suggesting a way to combine them to create a specific functionality like the "substr" method.