从iOS应用程序上传图像到php -不能完全正确-我错过了什么

首先，我知道这个问题已经被问过一千遍了。我再问一遍，因为我已经尝试了其他例子中的解决方案，但它们对我不起作用，我不知道为什么。每个人似乎都有稍微不同的方法。

NSData *imageData =  UIImagePNGRepresentation(form.image);
NSURL *url = [NSURL URLWithString:@"myscript.php"];
NSMutableString *postParams = [[NSMutableString alloc] initWithFormat:@"&image=%@", imageData]];
NSData *postData = [postParams dataUsingEncoding:NSASCIIStringEncoding allowLossyConversion:YES];
NSString *postLength = [[NSString alloc] initWithFormat:@"%d", [postData length]];
NSMutableURLRequest *connectRequest = [[NSMutableURLRequest alloc] init];
[connectRequest setURL:url];
[connectRequest setHTTPMethod:@"POST"];
[connectRequest setValue:postLength forHTTPHeaderField:@"Content-Length"];
[connectRequest setValue:@"application/x-www-form-urlencoded" forHTTPHeaderField:@"Content-Type"];
//[connectRequest setValue:@"image/png" forHTTPHeaderField:@"Content-Type"];
[connectRequest setHTTPBody:postData];
NSData *receivedData;
NSDictionary *jsonData;
NSURLConnection *connectConnection = [[NSURLConnection alloc] initWithRequest:connectRequest delegate:self];
NSError *error = nil;
if (!connectConnection) {
    receivedData = nil;
    NSLog(@"The connection failed!");
} else {
    NSLog(@"Connected!");
    receivedData = [NSURLConnection sendSynchronousRequest:connectRequest returningResponse:NULL error:&error];
}
if (!receivedData) {
    NSLog(@"Data fetch failed: %@", [error localizedDescription]);
} else {
    NSLog(@"The data is %lu bytes", (unsigned long)[receivedData length]);
    NSLog(@"%@", receivedData);
    if (NSClassFromString(@"NSJSONSerialization")) {
        id object = [NSJSONSerialization JSONObjectWithData:receivedData options:0 error:&error];
        if (!object) {
            NSLog(@"JSON Serialization failed: %@", [error localizedDescription]);
        }
        if ([object isKindOfClass:[NSDictionary class]]) {
            jsonData = object;
            NSLog(@"json data: %@", jsonData);
        }
    }
}

此刻我正在传递NSData在postParams和使用这个php脚本:

if (isset($_POST['image']) && !empty($_POST['image'])) {
     if (file_put_contents('images/test.png', $_POST['image'])) {
           echo '{"saved":"YES"}'; die();
     } else {
           echo '{"saved":"NO"}'; die();     
     }
}

这是保存数据到一个文件，但我不能打开它，因为它是损坏或一些这样的事情。这几乎是最后的努力，我真的没有想到它会这样工作，但这是我目前为止最接近正确的。

我已经尝试使用各种内容头/边界/$_FILES/enctype内容类型的方法，但我甚至不能得到它发送到脚本正确。

顺便说一下，我不只是发送图像数据，我还在postParams中发布了其他值，比如字符串，整型等。

有没有人有任何建议或知道任何好的来源?

感谢您提供的任何帮助。

按照以下答案给出的建议(以及程序其他部分的进一步信息)后的当前状态:

初始图像捕获:

- (void)viewWillDisappear:(BOOL)animated
{
    [super viewWillDisappear:animated];
    [self.view endEditing:YES];
    __unused form *form = self.form;
    form.signature = self.signatureDrawView.bp;
    UIGraphicsBeginImageContext(self.signatureDrawView.bounds.size);
    [self.signatureDrawView.layer renderInContext:UIGraphicsGetCurrentContext()];
    campaignForm.signatureImage = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
}

其中signatureDrawView是一个UIView和表单。签名是uibezier路径。

然后……

NSData *sigImage =  UIImagePNGRepresentation(campaignForm.signatureImage);

传递给以下函数:

- (void)uploadImage:(NSData *)imageData
{
    NSMutableURLRequest *request;
    NSString *urlString = @"https://.../upload.php";
    NSString *filename = @"uploadTest";
    request= [[NSMutableURLRequest alloc] init];
    [request setURL:[NSURL URLWithString:urlString]];
    [request setHTTPMethod:@"POST"];
    NSString *boundary = @"---------------------------14737809831466499882746641449";
    NSString *contentType = [NSString stringWithFormat:@"multipart/form-data; boundary=%@",boundary];
    [request addValue:contentType forHTTPHeaderField: @"Content-Type"];
    NSMutableData *postbody = [NSMutableData data];
    [postbody appendData:[[NSString stringWithFormat:@"'r'n--%@'r'n",boundary] dataUsingEncoding:NSUTF8StringEncoding]];
    [postbody appendData:[[NSString stringWithFormat:@"Content-Disposition: form-data; name='"file'"; filename='"%@.png'"'r'n", filename] dataUsingEncoding:NSUTF8StringEncoding]];
    [postbody appendData:[@"Content-Type: application/octet-stream'r'n'r'n" dataUsingEncoding:NSUTF8StringEncoding]];
    [postbody appendData:[NSData dataWithData:imageData]];
    [postbody appendData:[[NSString stringWithFormat:@"'r'n--%@--'r'n",boundary] dataUsingEncoding:NSUTF8StringEncoding]];
    [request setHTTPBody:postbody];
    NSData *returnData = [NSURLConnection sendSynchronousRequest:request returningResponse:nil error:nil];
    NSString *returnString;
    returnString = [[NSString alloc] initWithData:returnData encoding:NSUTF8StringEncoding];
    NSLog(@"%@", returnString);
}

upload.php:

    if ($_FILES["file"]["error"] > 0) {
        echo '{"file":"'.$_FILES['file']['error'].'"}';
        die();
    } else {
        $size = $_FILES["file"]["size"] / 1024;
        $upload_array = array(
                    "Upload"=>$_FILES["file"]["name"],
                    "Type"=>$_FILES["file"]["type"],
                    "Size"=>$size,
                    "Stored in"=>$_FILES["file"]["tmp_name"]
                    );
        //echo json_encode($upload_array);
        if (move_uploaded_file($_FILES["file"]["tmp_name"], "signatures/" . $_FILES["file"]["name"])) {
            echo '{"success":"YES"}';
            die();  
        } else { 
            echo '{"success":"NO"}';
            die();  
        }
        die();
    }

这给了我{success:NO}输出和$upload_array转储显示空值。