Question

我正在从webService解析JSON，它给我图像，文本等。文本可以被提取出来，但是如何从中获取图像呢？

这就是JSON响应的样子。

[
 {  "photo": "23_841676772.jpg",
    "date": "2013-06-06 08:11:15",
    "tags": "",
    "ID_article": "1",
    "commentcount": "5"
 },
]

我试图在tableView：cellForRow方法中将其设置为无效。

    NSMutableDictionary *tempDict3 = [self.jsonArray objectAtIndex:indexPath.row];
    cell.blogImageView.image = [UIImage imageNamed:[tempDict3 objectForKey:@"photo"]];

Answer 1

要从JASON回复中取消照片名称，您可以使用此代码

JSONResponse : [
 {  "photo": "23_841676772.jpg",
    "date": "2013-06-06 08:11:15",
    "tags": "",
    "ID_article": "1",
    "commentcount": "5"
 },
]

在.h文件

中创建一个Array对象

@interface ViewController : UIViewController
{
    NSMutableArray * photoNameData;
}

在.m档案中

photoNameData =[[NSMutableArray alloc] init];
NSMutableArray * tmpAry = JSONResponse;
if (tmpAry.count !=0) {
        for (int i=0; i<tmpAry.count; i++) {
            NSMutableDictionary * tmpDictn = [tmpAry objectAtIndex:i];
            [photoNameData addObject:[tmpDictn objectForKey:@"photo"]];
        }
    }

您可以使用以下代码下载文档目录中的图像。

for (int i=0; i<photoNameData.count; i++) {  //updated here

//First check that document directory contain image or not  
        NSString* tmpStr = [photoNameData objectAtIndex:i];  // used the photoNameData to get image name
        NSString* tmpImgURL = [NSString stringWithFormat:@"%@%@",@"http://www.my server.com/web_services/photos/",tmpStr];   //merge the image name and url
        NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
        NSString *documents = [paths objectAtIndex:0];
        NSString* foofile = [documents stringByAppendingPathComponent:tmpStr];
        BOOL imageExists = [[NSFileManager defaultManager] fileExistsAtPath:foofile];

//  if image not exist than download it
            if (!imageExists) {
                        NSLog(@"%@ not exist",tmpImgURL);
                        NSURLRequest *request = [NSURLRequest requestWithURL:[NSURL URLWithString:tmpImgURL] cachePolicy:NSURLCacheStorageNotAllowed timeoutInterval:10.0];
                        [NSURLConnection sendAsynchronousRequest:request queue:[NSOperationQueue mainQueue] completionHandler:^(NSURLResponse *response, NSData *data, NSError *err){
                            if (!err && data) {
                                //NSLog(@"data : %@",data);
                                NSString *finalPath = [documents stringByAppendingPathComponent:tmpStr];
                                NSLog(@"finalPath : %@",finalPath);
                                [data writeToFile:finalPath atomically:YES];
                            }else{
                                NSLog(@"err : %@",err);
                            }
                        }];
                    }
}

您可以使用此代码使用此图片..

NSString* tmpStr = [photoNameData objectAtIndex:indexPath.row];  //get the image name from photoNameData
NSString * documentsDirectoryPath = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0];
UIImage * image = [UIImage imageWithContentsOfFile:[NSString stringWithFormat:@"%@/%@",documentsDirectoryPath, tmpStr]];
cell.blogImageView.image = image;

Answer 2

我使用静态json你可以用你的json url替换str。

NSString *Str =[NSString stringWithFormat:@"[{\"photo\": \"23_841676772.jpg\",\"date\":\"2013-06-06 08:11:15\",\"tags\": \"\",\"ID_article\": \"1\",\"commentcount\": \"5\"},{\"photo\": \"dfdgfdgd.jpg\",\"date\":\"2013-06-06 08:11:15\",\"tags\": \"\",\"ID_article\": \"1\",\"commentcount\": \"5\"}]"];


NSDictionary *catgDict = [NSJSONSerialization JSONObjectWithData:[Str dataUsingEncoding:NSUTF8StringEncoding] options:kNilOptions error:nil];

for(NSDictionary *dict in catgDict)
{
    NSLog(@"dd: %@",dict);
    NSLog(@"Photo: %@",[dict valueForKey:@"photo"]);
}

Answer 3

请您的网络服务团队在您的回复中添加另一个标记“image_url”，以便您可以将图片网址转换为图片。如果他们说我们出于安全原因无法给出它，那么剩下的唯一选择就是对路径进行硬编码并将“图像名称”附加到它上面，这样你就可以获得完整的图像网址，现在可以将其转换为图像。

如何从iOS中的JSON响应中提取图像

3 个答案: