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JavaScript JavaScript and the DOM (Retiring) Getting a Handle on the DOM Selecting Elements with the Same Class Name

Monroe Gollaher
Monroe Gollaher
7,301 Points
Posted by Monroe Gollaher
Monroe Gollaher
7,301 Points

Color not changing and "app.js:4 Uncaught TypeError: Cannot read property 'style' of undefined at app.js:4"

Hi, for some reason my code for changing the li items to purple is working great. But when trying to change the "error-not-purple" class to red, it won't work. And the only error the console gives me tells me to reference line 4, which I know is working.

Any help would be greatly appreciated! Link to workspace: https://w.trhou.se/4fl8mngpgr

1 Answer

Steven Parker
Steven Parker
231,248 Points
Steven Parker
Steven Parker
231,248 Points

When you construct a "for" loop to go through an iterable, the index values should go up to but not including the length of the iterable. That's because index numbers begin at 0 instead of 1.

So the conditional clauses of the "for" loops should use the "<" operator instead of "<=".