厚積薄發，滴水穿石

Sorting

• –?sortedArrayHint
• –?sortedArrayUsingFunction:context:
• –?sortedArrayUsingFunction:context:hint:
• –?sortedArrayUsingDescriptors:
• –?sortedArrayUsingSelector:
• –?sortedArrayUsingComparator:
• –?sortedArrayWithOptions:usingComparator:

?

- (NSArray *)sortedArrayUsingSelector:(SEL)comparator

Parameters

comparator

A selector that identifies the method to use to compare two elements at a time. The method should returnNSOrderedAscending if the receiving array is smaller than the argument,?NSOrderedDescending if the receiving array is larger than the argument, and?NSOrderedSame if they are equal.

//selector定義了一個比較兩個數組元素的方法，如果此方法返回NSOrderedAscending說明此元素比參數元素小，如果返回NSOrderedDescending說明接收的數組元素比參數元素大，NSOrderedSame相等。

Example:

一個元素為NSString的數組可以通過調用NSString類中的caseInsensitiveCompare:方法作為Selector。

假設anArray已經存在：

 NSArray *sortedArray =

         [anArray sortedArrayUsingSelector:@selector(caseInsensitiveCompare:)];