NSURLConnection连接到服务器，但不发布数据 [英] NSURLConnection connecting to server, but not posting data

问题描述

每当我尝试向PHP服务器发布内容时，都会收到以下消息。似乎代码连接到服务器，但没有返回数据，并且后期数据不会通过。它通过我制作的Java应用程序工作，所以我可以保证他们的PHP没有错。如果您可以帮助我，或者需要更多代码来帮助我，那就请求它。谢谢。

Whenever I attempt to post something to my PHP Server, I receive the following message. It seems as if the code is connecting to the server, but no data is returned, and the post data isn't going through. It worked through a Java App that I made, so I can assure that their is nothing wrong with my PHP. If you could help me, or need any more code to help me, just ask for it. Thanks.

以下是为NSURLConnection准备变量的代码：

Here is the code that prepares my variables for the NSURLConnection:

NSString *phash = [NSString stringWithFormat:@"%d",phashnum];
        [phash stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
name = _nameField.text;
        [name stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
        email = _emailField.text;
        [email stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];

以下是我的NSURLConnection的代码：

Here is the code for my NSURLConnection:

NSString *urlPath = [NSString stringWithFormat:@"http://54.221.224.251"];
    NSURL *url = [NSURL URLWithString:urlPath];
    NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];
    NSString *stringdata = [NSString stringWithFormat:@"name=%@&email=%@&phash=%@",name,email,phash];
    NSOperationQueue *queue= [[NSOperationQueue alloc]init];
    NSString *postData = [[NSString alloc] initWithString:stringdata];
    [request setValue:@"application/x-www-form-urlencoded; charset=utf-8" forHTTPHeaderField:@"Content-Type"];
    [request setHTTPMethod:@"POST"];
    [request setHTTPBody:[postData dataUsingEncoding:NSUTF8StringEncoding]];
    [NSURLConnection sendAsynchronousRequest:request queue:queue completionHandler:^(NSURLResponse *response, NSData *data, NSError *connectionError) {
        if ([data length] > 0 && connectionError==nil){
            NSLog(@"Connection Success. Data Returned");
            NSLog(@"Data = %@",data);
            NSHTTPURLResponse *httpResponse = (NSHTTPURLResponse *)response;
            int code = [httpResponse statusCode];
            NSString *coder = [NSString stringWithFormat:@"%d",code];
            NSLog(@"%@",coder);
        }
        else if([data length] == 0 && connectionError == nil){
            NSLog(@"Connection Success. No Data returned.");
            NSLog(@"Connection Success. Data Returned");
            NSLog(@"Data = %@",data);
            NSHTTPURLResponse *httpResponse = (NSHTTPURLResponse *)response;
            int code = [httpResponse statusCode];
            NSString *coder = [NSString stringWithFormat:@"%d",code];
            NSLog(@"%@",coder);
        }
        else if(connectionError != nil && connectionError.code == NSURLErrorTimedOut){
            NSLog(@"Connection Failed. Timed Out");
            NSHTTPURLResponse *httpResponse = (NSHTTPURLResponse *)response;
            int code = [httpResponse statusCode];
            NSString *coder = [NSString stringWithFormat:@"%d",code];
            NSLog(@"%@",coder);

        }
        else if(connectionError != nil)
        {
            NSLog(@"%@",connectionError);
            NSHTTPURLResponse *httpResponse = (NSHTTPURLResponse *)response;
            int code = [httpResponse statusCode];
            NSString *coder = [NSString stringWithFormat:@"%d",code];
            NSLog(@"%@",coder);

        }
    }];

提前致谢。

推荐答案

正如@elk所说，你应该用 + 替换空格。但是您应该对保留字符进行百分比编码（如 RFC2396 中所定义）。

As @elk said, you should replace spaces with +. But you should percent-encode reserved characters (as defined in RFC2396).

不幸的是，标准的 stringByAddingPercentEscapesUsingEncoding 并没有逃脱所有保留字符的百分比。例如，如果名称是Bill& Melinda Gates或Bill + Melinda Gates，则 stringByAddingPercentEscapesUsingEncoding 不会逃脱& 或 + （因此 + 将被解释为空格，并且& 会被解释为分隔下一个 POST 参数。）

Unfortunately, the standard stringByAddingPercentEscapesUsingEncoding does not percent escape all of the reserved characters. For example, if the name was "Bill & Melinda Gates" or "Bill + Melinda Gates", stringByAddingPercentEscapesUsingEncoding would not percent escape the & or the + (and thus the + would have been interpreted as a space, and the & would have been interpreted as delimiting the next POST parameter).

相反，请使用 CFURLCreateStringByAddingPercentEscapes ，在 legalURLCharactersToBeEscaped 参数然后用 + 替换空格。例如，您可以定义 NSString 类别：

Instead, use CFURLCreateStringByAddingPercentEscapes, supplying the necessary reserved characters in the legalURLCharactersToBeEscaped parameter and then replace the spaces with +. For example, you might define a NSString category:

@implementation NSString (PercentEscape)

- (NSString *)stringForPostParameterValue:(NSStringEncoding)encoding
{
    NSString *string = CFBridgingRelease(CFURLCreateStringByAddingPercentEscapes(kCFAllocatorDefault,
                                                                                 (CFStringRef)self,
                                                                                 (CFStringRef)@" ",
                                                                                 (CFStringRef)@";/?:@&=+$,",
                                                                                 CFStringConvertNSStringEncodingToEncoding(encoding)));
    return [string stringByReplacingOccurrencesOfString:@" " withString:@"+"];
}

@end

注意，我主要关心的是使用& 和 + ，字符，但 RFC2396 （取代RFC1738）将这些附加字符列为保留字符，因此在中包含所有这些保留字符可能是谨慎的。 legalURLCharactersToBeEscaped 。

Note, I was primarily concerned with the & and +, characters, but RFC2396 (which supersedes RFC1738) listed those additional characters as being reserved, so it's probably prudent to include all of those reserved characters in the legalURLCharactersToBeEscaped.

将这一点拉到一起，我可能会将请求发布为：

Pulling this together, I might have code that posts the request as:

NSDictionary *params = @{@"name" : _nameField.text ?: @"",
                         @"email": _emailField.text ?: @"",
                         @"phash": [NSString stringWithFormat:@"%d",phashnum]};

NSURL *url = [NSURL URLWithString:kBaseURLString];
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];

[request setValue:@"application/x-www-form-urlencoded; charset=utf-8" forHTTPHeaderField:@"Content-Type"];
[request setHTTPMethod:@"POST"];
[request setHTTPBody:[self httpBodyForParamsDictionary:params]];

[NSURLConnection sendAsynchronousRequest:request queue:queue completionHandler:^(NSURLResponse *response, NSData *data, NSError *error) {
    if (error)
        NSLog(@"sendAsynchronousRequest error = %@", error);

    if (data) {
        // do whatever you want with the data
    }
}];

使用实用程序方法：

- (NSData *)httpBodyForParamsDictionary:(NSDictionary *)paramDictionary
{
    NSMutableArray *paramArray = [NSMutableArray array];
    [paramDictionary enumerateKeysAndObjectsUsingBlock:^(NSString *key, NSString *obj, BOOL *stop) {
        NSString *param = [NSString stringWithFormat:@"%@=%@", key, [obj stringForPostParameterValue:NSUTF8StringEncoding]];
        [paramArray addObject:param];
    }];

    NSString *string = [paramArray componentsJoinedByString:@"&"];

    return [string dataUsingEncoding:NSUTF8StringEncoding];
}

这篇关于NSURLConnection连接到服务器，但不发布数据的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！