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iOS

Could someone explain me about the index

I understand its purpose, but what does it mean/ how is it used in arrays. (swift) Actually, could you just explain what the index is/ how it is used... in short, can someone just explain to me what the index is....

2 Answers

Hi Egor. Just to be clear - index without context is a very loose concept... There is no "the index" if not in a specific context.

Normally, however, "index" is used to describe a pointer to a specific spot/row/item/whatever in an ordered list. I am using very broad terms here... It could be a value in an array or a row in a table - as long as there can be many items in an ordered fashion you use an index to specify which item/row/etc you are interested in.

var array = ["First Item", "Second Item", "Third Item"]

The array above has three items and you can access each of them using an index. In all programming languages (that I am aware of) basic enumeration begins with index 0. So to get the first item you would say array[0], and to get the second array[1] etc. etc. Makes sense?

A index is a position in a array. Say you have a array of colors var colorsArray = ["red", "blue", "gray", "orange"]

Okay now to get the index position for blue you need to call it like this println(colorsArray[1]) <----it's index 1 because index starts at 0 position

Hope this helps.