Question

在官方苹果开发者网站上测试请求并获取响应示例。

https://developer.apple.com/library/mac/documentation/Cocoa/Conceptual/URLLoadingSystem/Tasks/UsingNSURLConnection.html

在connectionDidFinishLoading中使用[connection release]方法，导致错误：应该是否已失效 - EXC_BAD_ACCESS

如果我评论行[连接释放]方法;一切似乎都有效我担心由于不存在连接释放而发生内存泄漏。

可能导致什么或如何避免此问题？

@imlementation test
NSMutableData *dataStore=nil;

//example usage:
//[self registerToServer:@"http://testserver.com/registeruser.ashx" withUserName:@"john doe" withPassword:@"123456"];

-(void)registerToServer:(NSString*)urlstr withUserName:(NSString*)
ausername withPassword:(NSString*)apassword
{
  NSURL *url=[NSURL URLWithString:urlstr];
    NSMutableURLRequest *request=[NSMutableURLRequest requestWithURL:url cachePolicy:NSURLCacheStorageNotAllowed timeoutInterval:3.0f];
[request setHTTPMethod:@"POST"];
[request setValue:ausername forHTTPHeaderField:@"pass"];
[request setValue:apassword forHTTPHeaderField:@"username"];
NSURLConnection *connection=[NSURLConnection connectionWithRequest:request delegate:self];
[connection start];

if(connection)
    dataStore=[[NSMutableData data]retain];
}

<小时/> - （void）connection：（NSURLConnection *）连接didReceiveData：（NSData *）数据 { [dataStore appendData：data]; }

- (void) connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response {
[dataStore setLength:0];}

-(void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error
{
NSLog(@"connection failed:%@ %@",
      [error localizedDescription],
      [[error userInfo]objectForKey:NSURLErrorFailingURLStringErrorKey]);

[connection release];
[dataStore release];
}

-(void)connectionDidFinishLoading:(NSURLConnection *)connection
  {
    //[connection release];   //WELL... I CANT COMMENT OUT THIS LINE!
    NSString *res=[[NSString alloc]initWithData:dataStore encoding:NSUTF8StringEncoding];

    NSLog(@"%@",res);
[dataStore release];
  }

Answer 1

使用工厂方法创建连接。仅当您使用alloc/init，new，copy或retain时，才应使用release。在这种情况下，系统将负责为您释放对象。

更好的是，使用ARC。

connectionDidFinishLoading中的连接释放方法会导致错误

1 个答案: