【iPhone代码片段之七】用NSUserDefaults作为缓存工具

本工具仅支持缓存NSString类型数据。

CacheUtil.h，代码如下：

#import <Foundation/Foundation.h>@interface CacheUtil : NSObject {}+(void)cacheItems:(NSString*)item for:(NSString*)key;+(NSString*)cachedItemsFor:(NSString*)key;+(void)removeCacheItem:(NSString*)key;@end

CacheUtil.m，代码如下：

#import "CacheUtil.h"@implementation CacheUtil//用键值key，缓存item+(void)cacheItems:(NSString*)item for:(NSString*)key {NSUserDefaults* defaults= [NSUserDefaults standardUserDefaults];[defaults setObject:item forKey:key];}//取出键值为key的缓存内容+(NSString*)cachedItemsFor:(NSString*)key {NSUserDefaults* defaults= [NSUserDefaults standardUserDefaults];NSString* item = [defaults objectForKey:key];return item;}//删除键值为key的缓存+(void)removeCacheItem:(NSString*)key {NSUserDefaults* defaults= [NSUserDefaults standardUserDefaults];[defaults removeObjectForKey:key];}  @end