NSURLConnection JSON提交到服务器

Question

我在这里不知所措,我想我会为我的应用程序尝试新的Web服务.

我可以提取数据没有问题,但我试图发布到服务器,似乎可以得到这甚至火.

我打算发生什么是在提交按钮按下动作被解雇:

- (IBAction)didPressSubmit:(id)sender {

     //JSON SERIALIZATION OF DATA
     NSMutableDictionary *projectDictionary = [NSMutableDictionary dictionaryWithCapacity:1];
    [projectDictionary setObject:[projectName text] forKey:@"name"];
    [projectDictionary setObject:[projectDescShort text] forKey:@"desc_short"];
    [projectDictionary setObject:[projectDescLong text] forKey:@"desc_long"];

    NSError *jsonSerializationError = nil;
    NSData *jsonData = [NSJSONSerialization dataWithJSONObject:projectDictionary options:NSJSONWritingPrettyPrinted error:&jsonSerializationError];

    if(!jsonSerializationError) {
        NSString *serJSON = [[NSString alloc] initWithData:jsonData encoding:NSUTF8StringEncoding];
        NSLog(@"Serialized JSON: %@", serJSON);
    } else {
        NSLog(@"JSON Encoding Failed: %@", [jsonSerializationError localizedDescription]);
    }

    // JSON POST TO SERVER
    NSURL *projectsUrl = [NSURL    URLWithString:@"http://70.75.66.136:3000/projects.json"];
    NSMutableURLRequest *dataSubmit = [NSMutableURLRequest requestWithURL:projectsUrl cachePolicy:NSURLRequestUseProtocolCachePolicy timeoutInterval:30.0];
    [dataSubmit setHTTPMethod:@"POST"]; // 1
    [dataSubmit setValue:@"application/json" forHTTPHeaderField:@"Accept"]; // 2
    [dataSubmit setValue:[NSString stringWithFormat:@"%d", [jsonData length]] forHTTPHeaderField:@"Content-Length"]; // 3
    [dataSubmit setHTTPBody: jsonData];

     [[NSURLConnection alloc] initWithRequest:dataSubmit delegate:self];
}

之后它贯穿:

- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response
{
    NSLog(@"DidReceiveResponse");

}


- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)theData
{
    NSLog(@"DidReceiveData");
}

- (void)connectionDidFinishLoading:(NSURLConnection *)connection
{
   [UIApplication sharedApplication].networkActivityIndicatorVisible = NO;
}


- (void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error
{
    UIAlertView *errorView = [[UIAlertView alloc] initWithTitle:@"Error" message:@"BLAH CHECK YOUR NETWORK" delegate:nil cancelButtonTitle:@"Dismiss" otherButtonTitles:nil];
    [errorView show];
    [UIApplication sharedApplication].networkActivityIndicatorVisible = NO;
}

我显然缺少一些东西,但我甚至不知道在哪里看.我所需要的只是朝着正确方向发展的一点,任何帮助都会很棒.

UPDATE

我能够通过以下方式获得解雇请求.

好的,我能够使用以下内容获取触发请求:

- (IBAction)didPressSubmit:(id)sender {


    NSMutableDictionary *projectDictionary = [NSMutableDictionary dictionaryWithCapacity:1];
    [projectDictionary setObject:[projectName text] forKey:@"name"];
    [projectDictionary setObject:[projectDescShort text] forKey:@"desc_small"];
    [projectDictionary setObject:[projectDescLong text] forKey:@"desc_long"];

    NSError *jsonSerializationError = nil;
    NSData *jsonData = [NSJSONSerialization dataWithJSONObject:projectDictionary options:NSJSONWritingPrettyPrinted error:&jsonSerializationError];

    if(!jsonSerializationError) {
        NSString *serJSON = [[NSString alloc] initWithData:jsonData encoding:NSUTF8StringEncoding];
        NSLog(@"Serialized JSON: %@", serJSON);
    } else {
        NSLog(@"JSON Encoding Failed: %@", [jsonSerializationError localizedDescription]);
    }

    NSURL *projectsUrl = [NSURL URLWithString:@"http://70.75.66.136:3000/projects.json"];
    NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:projectsUrl cachePolicy:NSURLRequestUseProtocolCachePolicy timeoutInterval:30.0];
    [request setHTTPMethod:@"POST"]; // 1
    [request setValue:@"application/json" forHTTPHeaderField:@"Accept"]; // 2
    [request setValue:[NSString stringWithFormat:@"%d", [jsonData length]] forHTTPHeaderField:@"Content-Length"]; // 3
    [request setHTTPBody: jsonData]; // 4


    (void) [[NSURLConnection alloc] initWithRequest:request delegate:self];

}

但由于某种原因,post方法只收到一堆零值,我从服务器端得到这个. Processing by ProjectsController#create as JSON Parameters: {"{\n \"desc_long\" : \"a\",\n \"name\" : \"a\",\n \"desc_small\" : \"a\"\n}"=>nil}

更新2

稍微阅读一下:http://elusiveapps.com/blog/2011/04/ios-json-post-to-ruby-on-rails/

我能够看到是否错过了以下一行. [request setValue:@"application/json" forHTTPHeaderField:@"Content-Type"];

所以最后的didPressSubmit代码如下;

- (IBAction)didPressSubmit:(id)sender {


    NSMutableDictionary *projectDictionary = [NSMutableDictionary dictionaryWithCapacity:1];
    [projectDictionary setObject:[projectName text] forKey:@"name"];
    [projectDictionary setObject:[projectDescShort text] forKey:@"desc_small"];
    [projectDictionary setObject:[projectDescLong text] forKey:@"desc_long"];

    NSError *jsonSerializationError = nil;
    NSData *jsonData = [NSJSONSerialization dataWithJSONObject:projectDictionary options:NSJSONWritingPrettyPrinted error:&jsonSerializationError];

    if(!jsonSerializationError) {
        NSString *serJSON = [[NSString alloc] initWithData:jsonData encoding:NSUTF8StringEncoding];
        NSLog(@"Serialized JSON: %@", serJSON);
    } else {
        NSLog(@"JSON Encoding Failed: %@", [jsonSerializationError localizedDescription]);
    }

    NSURL *projectsUrl = [NSURL URLWithString:@"http://70.75.66.136:3000/projects.json"];
    NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:projectsUrl cachePolicy:NSURLRequestUseProtocolCachePolicy timeoutInterval:30.0];
    [request setHTTPMethod:@"POST"]; // 1
    [request setValue:@"application/json" forHTTPHeaderField:@"Accept"]; // 2
    [request setValue:@"application/json" forHTTPHeaderField:@"Content-Type"];
    [request setValue:[NSString stringWithFormat:@"%d", [jsonData length]] forHTTPHeaderField:@"Content-Length"]; // 3
    [request setHTTPBody: jsonData]; // 4


    (void) [[NSURLConnection alloc] initWithRequest:request delegate:self];

}

Answer 1

我遇到了同样的问题，但我通过将选项设置为零来解决它。

代替

NSData *jsonData = [NSJSONSerialization dataWithJSONObject:projectDictionary options:NSJSONWritingPrettyPrinted error:&jsonSerializationError];

经过

NSData *jsonData = [NSJSONSerialization dataWithJSONObject:projectDictionary options:nil error:&jsonSerializationError];

nil如果要将 json 发送到服务器，请使用选项 to ，如果要显示 json，请使用NSJSONWritingPrettyPrinted。

希望对你有帮助。