IOS 开发学习二十 数据持久化：读写属性列表示例

////  PropertiesUtils.m//  smarthome////  Created by 谢厂节 on 15/5/25.//  Copyright (c) 2015年 WHR. All rights reserved.//#import "PropertiesUtils.h"@implementation PropertiesUtils-(void)save:(int)index :(NSString *)value{    NSString* fileName = [self filePath:@"Properties.plist"];    if ([[NSFileManager defaultManager]fileExistsAtPath:fileName]) {        NSMutableArray* data = [[NSMutableArray alloc]initWithContentsOfFile:fileName];        [data replaceObjectAtIndex:index withObject:value];                [data writeToFile:fileName atomically:YES];    }}-(NSString*)load:(int)index{    NSString* fileName = [self filePath:@"Properties.plist"];    if ([[NSFileManager defaultManager]fileExistsAtPath:fileName]) {        NSArray* data = [[NSArray alloc]initWithContentsOfFile:fileName];        return [data objectAtIndex:index];    }    else        return nil;}-(NSArray*)loadAll{    NSString* fileName = [self filePath:@"Properties.plist"];    if ([[NSFileManager defaultManager]fileExistsAtPath:fileName]) {        NSArray* data = [[NSArray alloc]initWithContentsOfFile:fileName];        return data;    }    else        return nil;}-(NSString *)filePath:(NSString *)fileName{    NSArray* myPaths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);    NSString* myDocPath = [myPaths objectAtIndex:0];    NSString* filePath = [myDocPath stringByAppendingPathComponent:fileName];    return filePath;}@end