重写NSArray与NSDictionary的descriptionWithLocale方法

更新1--2017年9月7日
最近发现，自从升级到Xcode8以后，字典和数组的descriptionWithLocale都不再被调用。后来使用
- (NSString *)descriptionWithLocale:(id)locale indent:(NSUInteger)level来取代，一切又恢复到正常。望周知。

重写NSArray的descriptionWithLocale方法:

NSArray+log.h

#import <Foundation/Foundation.h>
@interface NSArray (log)
@end

 NSArray+log.m

#import "NSArray+log.h"
@implementation NSArray (log)

- (NSString *)descriptionWithLocale:(id)locale
{
    NSMutableString *string = [NSMutableString string];
    
    // 开头有个[
    [string appendString:@"[\n"];
    
    // 遍历所有的元素
    [self enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {
        [string appendFormat:@"\t%@,\n", obj];
    }];
    
    // 结尾有个]
    [string appendString:@"]"];
    
    // 查找最后一个逗号
    NSRange range = [string rangeOfString:@"," options:NSBackwardsSearch];
    if (range.location != NSNotFound)
        [string deleteCharactersInRange:range];
    
    return string;
}

@end

重写NSDictionary的descriptionWithLocale方法:

NSDictionary.h

#import <Foundation/Foundation.h>
@interface NSDictionary (log)
@end

NSDictionary.m

#import "NSDictionary+log.h"
@implementation NSDictionary (log)

- (NSString *)descriptionWithLocale:(id)locale
{
    NSMutableString *string = [NSMutableString string];
    
    // 开头有个{
    [string appendString:@"{\n"];
    
    // 遍历所有的键值对
    [self enumerateKeysAndObjectsUsingBlock:^(id key, id obj, BOOL *stop) {
        [string appendFormat:@"\t%@", key];
        [string appendString:@" : "];
        [string appendFormat:@"%@,\n", obj];
    }];
    
    // 结尾有个}
    [string appendString:@"}"];
    
    // 查找最后一个逗号
    NSRange range = [string rangeOfString:@"," options:NSBackwardsSearch];
    if (range.location != NSNotFound)
        [string deleteCharactersInRange:range];
    
    return string;
}

@end