Nsurlconnection 未调用NSURL委托didReceiveData方法

我知道这已经在很多其他帖子中讨论过了，但我需要发布它，因为不幸的是这些帖子并没有帮到我。我正在尝试连接到一个rails服务器，该服务器以JSON格式返回一些数据以响应GET请求

#pragma mark -
#pragma mark NSURLConnectionDataDelegate

-(void) connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response {

    NSLog(@"didReceiveResponse");
    [resultData setLength:0];

}


-(void) connection:(NSURLConnection *)connection didReceiveData:(NSData *)data {

    NSLog(@"didReceiveData");
[resultData appendData:data];


}

-(void) connection:(NSURLConnection *)connection didFailWithError:(NSError *)error {

    NSLog(@"didFailWithError");

    NSString *errDesc = [NSString stringWithFormat:@"Connection failed: %@", [error description]];
    NSLog(@"%@",errDesc);

}

-(void) connectionDidFinishLoading:(NSURLConnection *)connection {

    NSLog(@"didReceiveLoading");
}

在ConnectionDiFinishDownloading方法（未列出）中，我执行JSON解析，但由于从未调用didReceiveData方法，因此该解析失败，因为resultData为空

调用didReceiveResponse方法是因为我看到消息正在被记录。服务器在本地主机上运行，因此我可以确认已收到请求，并且使用Charles，我知道已正确接收JSON格式的响应。因此，服务器端似乎没有问题。但从未调用didReceiveData方法。Didror方法也是如此

有人能帮我吗？我不知道我做错了什么。这是我第一次与NSURL合作，非常感谢。我正在用ARC开发iOS 5

萨蒂扬

编辑：

NSURL *url = [NSURL URLWithString:[NSString stringWithFormat:@"%@%@?%@", kDevelopmentMode ? kLocalHost : kHost, endpoint, parameters]];
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];
NSURLConnection *urlConnection = [[NSURLConnection alloc] initWithRequest:request delegate:self];

---

我猜你的应用程序无法恢复数据。用你的url试试这个，它会让你知道返回的原始数据，如果返回数据，会告诉你jsonserialization

NSData *returnedData = [[NSData alloc] initWithContentsOfURL:[NSURL URLWithString:@"http://yourURLHere"]];

if (returnedData) {
    NSLog(@"returnedData:%@", returnedData);

    NSDictionary *jsonDict = [NSJSONSerialization JSONObjectWithData:returnedData options:kNilOptions error:Nil];
    NSLog(@"jsonDict:%@", jsonDict);
}
else
    NSLog(@"Got Nothing");

如果日志显示原始数据和json数据，那么问题在于NSURL请求。但是如果日志显示“什么都没有”，那么您试图获取的内容就有问题

编辑

#import <UIKit/UIKit.h>

@interface AsyncImage : UIImageView 
{    
    NSMutableData *activeDownload;
    NSURLConnection *imageConnection;
}
@property (nonatomic, retain) NSMutableData *activeDownload;
@property (nonatomic, retain) NSURLConnection *imageConnection;
- (void)loadImageFromURL:(NSURL*)url;
@end



#import "AsyncImage.h"

@implementation AsyncImage
@synthesize activeDownload;
@synthesize imageConnection;

- (void)dealloc
{
    [super dealloc];
    NSLog(@"dealloc AsyncImage");

    [activeDownload release];
    [imageConnection cancel];
    [imageConnection release];
}

- (void)cancelDownload
{
    [self.imageConnection cancel];
    self.imageConnection = nil;
    self.activeDownload = nil;
}


#pragma mark -
#pragma mark Download support (NSURLConnectionDelegate)

- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data
{
    [self.activeDownload appendData:data];
}

- (void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error
{
    // Clear the activeDownload property to allow later attempts
    self.activeDownload = nil;

    // Release the connection now that it's finished
    self.imageConnection = nil;
}

- (void)connectionDidFinishLoading:(NSURLConnection *)connection
{
    self.image = [UIImage imageWithData:self.activeDownload];

    self.activeDownload = nil;

    // Release the connection now that it's finished
    self.imageConnection = nil;
}

- (void)loadImageFromURL:(NSURL*)url {
    if (self.imageConnection!=nil) { [imageConnection release]; } //in case we are downloading a 2nd image

    self.activeDownload = [NSMutableData data];
    // alloc+init and start an NSURLConnection; release on completion/failure
    NSURLConnection *conn = [[NSURLConnection alloc] initWithRequest:
                             [NSURLRequest requestWithURL:url] delegate:self];
    self.imageConnection = conn;
    [conn release];
}

@end

#导入
@接口异步映像：UIImageView
{    
NSMutableData*动态下载；
NSURLConnection*图像连接；
}
@属性（非原子，保留）NSMutableData*activeDownload；
@属性（非原子，保留）NSURLConnection*imageConnection；
-（void）loadImageFromURL:（NSURL*）url；
@结束
#导入“AsyncImage.h”
@异步映像的实现
@综合动态下载；
@综合图像连接；
-（无效）解除锁定
{
[super dealoc]；
NSLog（@“dealoc AsyncImage”）；
[动态下载版本]；
[图像连接取消]；
[图像连接释放]；
}
-（作废）取消下载
{
[self.imageConnection取消]；
self.imageConnection=nil；
self.activeDownload=nil；
}
#布拉格标记-
#pragma标记下载支持（NSURLConnectionLegate）
-（void）连接：（NSURLConnection*）连接didReceiveData:（NSData*）数据
{
[self.activedata:data]；
}
-（无效）连接：（NSURLConnection*）连接失败错误：（NSError*）错误
{
//清除activeDownload属性以允许以后尝试
self.activeDownload=nil；
//现在连接已完成，请释放连接
self.imageConnection=nil；
}
-（无效）连接IDFinishLoading:（NSURLConnection*）连接
{
self.image=[UIImage-imageWithData:self.activeDownload]；
self.activeDownload=nil；
//现在连接已完成，请释放连接
self.imageConnection=nil；
}
-（void）loadImageFromURL:（NSURL*）url{
如果（self.imageConnection！=nil）{[imageConnection release]；}//我们正在下载第二个映像
self.activeDownload=[NSMutableData]；
//alloc+init并启动NSURLConnection；完成/失败时释放
NSURLConnection*conn=[[NSURLConnection alloc]initWithRequest:
[nsurlRequestWithURL:url]委托：自我]；
self.imageConnection=conn；
[控制释放]；
}
@结束

我猜你的应用程序无法恢复数据。用你的url试试这个，它会让你知道返回的原始数据，如果返回数据，会告诉你jsonserialization

NSData *returnedData = [[NSData alloc] initWithContentsOfURL:[NSURL URLWithString:@"http://yourURLHere"]];

if (returnedData) {
    NSLog(@"returnedData:%@", returnedData);

    NSDictionary *jsonDict = [NSJSONSerialization JSONObjectWithData:returnedData options:kNilOptions error:Nil];
    NSLog(@"jsonDict:%@", jsonDict);
}
else
    NSLog(@"Got Nothing");

如果日志显示原始数据和json数据，那么问题在于NSURL请求。但是如果日志显示“什么都没有”，那么您试图获取的内容就有问题

编辑

#import <UIKit/UIKit.h>

@interface AsyncImage : UIImageView 
{    
    NSMutableData *activeDownload;
    NSURLConnection *imageConnection;
}
@property (nonatomic, retain) NSMutableData *activeDownload;
@property (nonatomic, retain) NSURLConnection *imageConnection;
- (void)loadImageFromURL:(NSURL*)url;
@end



#import "AsyncImage.h"

@implementation AsyncImage
@synthesize activeDownload;
@synthesize imageConnection;

- (void)dealloc
{
    [super dealloc];
    NSLog(@"dealloc AsyncImage");

    [activeDownload release];
    [imageConnection cancel];
    [imageConnection release];
}

- (void)cancelDownload
{
    [self.imageConnection cancel];
    self.imageConnection = nil;
    self.activeDownload = nil;
}


#pragma mark -
#pragma mark Download support (NSURLConnectionDelegate)

- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data
{
    [self.activeDownload appendData:data];
}

- (void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error
{
    // Clear the activeDownload property to allow later attempts
    self.activeDownload = nil;

    // Release the connection now that it's finished
    self.imageConnection = nil;
}

- (void)connectionDidFinishLoading:(NSURLConnection *)connection
{
    self.image = [UIImage imageWithData:self.activeDownload];

    self.activeDownload = nil;

    // Release the connection now that it's finished
    self.imageConnection = nil;
}

- (void)loadImageFromURL:(NSURL*)url {
    if (self.imageConnection!=nil) { [imageConnection release]; } //in case we are downloading a 2nd image

    self.activeDownload = [NSMutableData data];
    // alloc+init and start an NSURLConnection; release on completion/failure
    NSURLConnection *conn = [[NSURLConnection alloc] initWithRequest:
                             [NSURLRequest requestWithURL:url] delegate:self];
    self.imageConnection = conn;
    [conn release];
}

@end

#导入
@接口异步映像：UIImageView
{    
NSMutableData*动态下载；
NSURLConnection*图像连接；
}
@属性（非原子，保留）NSMutableData*activeDownload；
@属性（非原子，保留）NSURLConnection*imageConnection；
-（void）loadImageFromURL:（NSURL*）url；
@结束
#导入“AsyncImage.h”
@异步映像的实现
@综合动态下载；
@综合图像连接；
-（无效）解除锁定
{
[super dealoc]；
NSLog（@“dealoc AsyncImage”）；
[动态下载版本]；
[图像连接取消]；
[图像连接释放]；
}
-（作废）取消下载
{
[self.imageConnection取消]；
self.imageConnection=nil；
self.activeDownload=nil；
}
#布拉格标记-
#pragma标记下载支持（NSURLConnectionLegate）
-（void）连接：（NSURLConnection*）连接didReceiveData:（NSData*）数据
{
[self.activedata:data]；
}
-（无效）连接：（NSURLConnection*）连接失败错误：（NSError*）错误
{
//清除activeDownload属性以允许以后尝试
self.activeDownload=nil；
//现在连接已完成，请释放连接
self.imageConnection=nil；
}
-（无效）连接IDFinishLoading:（NSURLConnection*）连接
{
self.image=[UIImage-imageWithData:self.activeDownload]；
self.activeDownload=nil；
//现在连接已完成，请释放连接
self.imageConnection=nil；
}
-（void）loadImageFromURL:（NSURL*）url{
如果（self.imageConnection！=nil）{[imageConnection release]；}//我们正在下载第二个映像
self.activeDownload=[NSMutableData]；
//alloc+init并启动NSURLConnection；完成/失败时释放
NSURLConnection*conn=[[NSURLConnection alloc]initWithRequest:
[nsurlRequestWithURL:url]委托：自我]；
self.imageConnection=conn；
[控制释放]；
}
@结束

在.h文件中设置

NSURLConnectionLegate

。

在.h文件中设置

NSURLConnectionLegate

。

您好，我尝试了您建议的方法，并打印了原始数据和json数据