什么是OR EQUAL

Question

dataUpdated |= [backgroundApplicationData downloadLinks];

这个Or/Equal是什么意思？从未见过它.

Answer 1

它是按位OR,但缩写为+=.

它相当于 dataUpdated = dateUpdated | [backgroundApplicationData downloadLinks];

以下是按位运算符的列表:http://www.techotopia.com/index.php/Objective-C_Operators_and_Expressions#Compound_Bitwise_Operators