上传图片时出现问题(iphone sdk，multipartform-data)

Question

我需要上传图像到自定义服务器。我的代码是这样的：

NSString* boundary = @"blablablablabla";
NSString* boundaryString = [NSString stringWithFormat:@"\r\n--%@\r\n", boundary];
NSString* boundaryStringFinal = [NSString stringWithFormat:@"\r\n--%@--\r\n", boundary];

NSMutableData* postData = [NSMutableData dataWithCapacity:[imageData length] + 1024];

NSString* s = [NSString stringWithFormat:@"Content-Disposition: form-data; name=\"s\"\r\n\r\n%@\r\n", @"addimage"];
NSString* ad = [NSString stringWithFormat:@"Content-Disposition: form-data; name=\"ad\"\r\n\r\n%@\r\n", adIdx];
NSString* u = [NSString stringWithFormat:@"Content-Disposition: form-data; name=\"u\"\r\n\r\n%@\r\n", uid];

[postData appendData:[boundaryString dataUsingEncoding:NSUTF8StringEncoding]];
[postData appendData:[s dataUsingEncoding:NSUTF8StringEncoding]];
[postData appendData:[ad dataUsingEncoding:NSUTF8StringEncoding]];
[postData appendData:[u dataUsingEncoding:NSUTF8StringEncoding]];

[postData appendData:[boundaryString dataUsingEncoding:NSUTF8StringEncoding]];
[postData appendData:[[NSString stringWithFormat:@"Content-Disposition: form-data; name=\"image\";\r\nfilename=\"image.jpg\"\r\nContent-Type: image/jpg\r\n\r\n"] dataUsingEncoding:NSUTF8StringEncoding]];
[postData appendData:imageData];
[postData appendData:[boundaryStringFinal dataUsingEncoding:NSUTF8StringEncoding]];

NSMutableURLRequest* request = [NSMutableURLRequest requestWithURL:[NSURL URLWithString:@"http:a.b.c/d.php"]];
[request setHTTPMethod:@"POST"];

NSString* dataLength = [NSString stringWithFormat:@"%d", [postData length]];
[request addValue:[NSString stringWithFormat:@"multipart/form-data; boundary=%@", boundary] forHTTPHeaderField:@"Content-Type"];
[request addValue:@"a.b.c" forHTTPHeaderField:@"Host"];
[request addValue:dataLength forHTTPHeaderField:@"Content-Length"];
[request setHTTPBody:postData];

[NSURLConnection connectionWithRequest:request delegate:self];

它看起来很好，但是作为对这个请求的响应，我有这样一行："Missing paramter u“。谁能告诉我问题出在哪里？

Answer 1

missing parameter u消息几乎肯定来自服务器上的PHP。我猜想它应该在一个"u"\r\n\r\n结构中。你需要知道服务器需要什么才能解决这个问题。

我建议您将post请求作为字符串转储，粘贴到浏览器中，看看是否可以让它工作。这样，您就可以确保理解请求的正确形式，以便可以在代码中构建它。