plist文件读写

使用场景,通常用在读不变的数据的plist文件,如地名,城市

需求

1、用plist文件初始化一个数组，并输出数组中的元素。

2、分别用同步和异步从网上下载图片存到本地。使用异步的时候，显示下载进度。

#import <UIKit/UIKit.h>

@interface AppDelegate : UIResponder <UIApplicationDelegate,NSURLConnectionDataDelegate>
{
    long long totalLenth;
    long long receivedLenth;
    NSMutableData *mData;
}
@property (strong, nonatomic) UIWindow *window;

@end

#import "AppDelegate.h"
#define PATH1 @"http://h.hiphotos.baidu.com/image/w%3D2048/sign=4e4661fb3bdbb6fd255be2263d1caa18/42a98226cffc1e17951e59314890f603738de909.jpg"
@implementation AppDelegate

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
    // Override point for customization after application launch.
    self.window.backgroundColor = [UIColor whiteColor];
    //1关键-路径
    NSString *path = [[NSBundle mainBundle]pathForResource:@"abc" ofType:@"plist"];
    
    NSArray *arr = [NSArray arrayWithContentsOfFile:path];
    NSLog(@"arr = %@",arr);
    
    NSString *path2 = [[NSBundle mainBundle]pathForResource:@"Dictionary" ofType:@"plist"];
    NSDictionary *dict = [NSDictionary dictionaryWithContentsOfFile:path2];
    NSLog(@"dict = %@",dict);
    //2
    NSURLRequest *req = [NSURLRequest requestWithURL:[NSURL URLWithString:PATH1] cachePolicy:NSURLRequestReloadIgnoringCacheData timeoutInterval:120.0f];
    
    [NSURLConnection connectionWithRequest:req delegate:self];

    
    [self.window makeKeyAndVisible];
    return YES;
}
-(void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response
{
    mData = [[NSMutableData alloc]initWithLength:0];//不是0的话,里面参杂一些数据,会有问题
    totalLenth = [response expectedContentLength];//
}
-(void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data
{
    [mData appendData:data];
    receivedLenth = mData.length;
    float progress = receivedLenth * 100.0 / totalLenth;//低精靠向高精
    NSLog(@"%lf%%",progress);
}
-(void)connectionDidFinishLoading:(NSURLConnection *)connection
{
　　//NSLog(@"content = %@",[[NSString alloc]initWithData:mData encoding:NSUTF8StringEncoding]);图片不能转换成字符串,所以读出来为空,文本可以读取值
    [mData writeToFile:@"/Users/yf02/Desktop/Oc_12/123.png" atomically:YES];
}
-(void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error
{
    
}

plist文件配置参考:http://blog.csdn.net/totogo2010/article/details/7634185