图片封装下载——同步下载

声明：

#import <Foundation/Foundation.h>

#import <UIKit/UIKit.h>

//NSObject依赖于UIKit,

@interface ZYImageDownloader :
NSObject

//同步下载
+(UIImage*)imageDownloaderDownloadImageWithURLString:(NSString*)imageURL;

@end

==================

实现：

#import "ZYImageDownloader.h"

@interface
ZYImageDownloader ()

@property(nonatomic,strong)
UIImage *image;

@end
@implementation ZYImageDownloader

#pragma mark 同步下载
+(UIImage*)imageDownloaderDownloadImageWithURLString:(NSString *)imageURL
{

//根据传递进来的网址字符串创建请求对象

NSURLRequest *request = [[NSURLRequest
alloc]initWithURL:[NSURL
URLWithString:imageURL]];

//使用Data对象接收同步请求的图片数据

NSData *data = [NSURLConnection
sendSynchronousRequest:request returningResponse:nil
error:nil];

//返回请求后的图片对象

return [UIImage
imageWithData:data];
}

===========================

外部调用：

@interface
ViewController ()

@property (weak,
nonatomic) IBOutlet
UIImageView *photo;

@end

_photo.image = [ZYImageDownloader
imageDownloaderDownloadImageWithURLString:IMG_SYN];