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JavaScript JavaScript Basics Working with Strings Combine and Manipulate Strings

Posted by Kimberly DiPasqua
Kimberly DiPasqua
1,934 Points

"Cannot read property '1' of null" What am I doing incorrectly?

I've refreshed, restarted my computer, redone this several times. What am I missing? Thanks! :)

app.js 
let firstName = "Kim";
let lastName = "DiPasqua";
let role = 'developer';
let msg = `${firstName} ${lastName}: ${role}`;
let roleUpper = role.toUpperCase();
let msg = `${firstName} ${lastName}: ${roleUpper}`;

2 Answers

Kimberly DiPasqua
Kimberly DiPasqua
1,934 Points
Kimberly DiPasqua
Kimberly DiPasqua
1,934 Points

Hold on, I got it. I needed to change the variable name of line 6. I changed it to newMsg.

I hope this helps someone else, at least! :)

Mark Casavantes
Mark Casavantes
2,880 Points
Mark Casavantes
Mark Casavantes
2,880 Points

Hello Kimberly,

Getting a property '1' of null occurs when there is a problem with a variable.

Also, removing the "let" on line 6 would work. Once a variable is initialized, you do not have to initialize it again.

Your solution of changing the variable name works.

On lines 5 and 6, you could write:

role = role.toUpperCase();
msg = `${firstName} ${lastName}: ${role}`;

I hope this is helpful.