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JavaScript Building a MEAN Application Creating and Editing Data in a MEAN App Create and Update Data in Angular

Posted by Mark Franklin
Mark Franklin
3,162 Points

Purpose of .then for put request?

When adding the put request functionality to the saveTodos method of the dataService, what is the purpose of the .then(function(result){todo = result.data.todo}) ?

I originally built it without including this and everything worked just fine. It doesn't appear to actually do anything that I can see, what's it for?

3 Answers

Steven Parker
Steven Parker
229,708 Points
Steven Parker
Steven Parker
229,708 Points

I haven't taken this course yet myself, but normally a then method is called on a promise to establish the function to be performed when it gets (or if it has already been) resolved.

If leaving out had no adverse effects, then I would guess that having the todo variable set to todo value contained in the returned data isn't important to the rest of the program.

Shawn Stern
Shawn Stern
6,123 Points
Shawn Stern
Shawn Stern
6,123 Points

Would appreciate a response to this question. My app also has no immediately noticeable ill effects from completely removing the .then from that part of saveTodos... Why was it put there?

matthewharrington2
PLUS
matthewharrington2
Courses Plus Student 13,219 Points
matthewharrington2
matthewharrington2
Courses Plus Student 13,219 Points

I think that it's just there to return a value(the object that was saved) so that you know that the put worked. You can console.log(result.data.todo); to see the object. While it doesn't seem to serve much of a purpose in this app, maybe he included it to show how you can access the res object( from router.put in the src/api/index.js file) of the put.