JavaScript多维数组问题

Question

I want to create an array like this:

send[1]['conversation_group_id']=1;

But i get an error that cannot set property conversation_group_id of undefined. What am i doing wrong?

Thanks!

Answer 1

Even though you have initialized send with [], which makes it an array, send[1] will be undefined, you will need to initialize it as an object too before you can set a property inside it. At the moment you are trying to set a property of undefined.

 var send = []; console.log(send[1]); send[1] = {}; send[1]['conversation_group_id']=1; console.log(send[1]['conversation_group_id']); 

Answer 2

Your data structure is an array of objects. To initialize it, you can also do it this way.

send = [null, {conversation_group_id: 1}]

Nothing wrong with @Dij's answer , but just though it's worth mentioning an alternative on how to initialize the structure you're looking for.