在 Swift 中上传带有参数的图像

In your comment below, you inform us that you are using the $_FILES syntax to retrieve the files. That means that you want to create a multipart/form-data request. The process is basically:

1. Specify a boundary for your multipart/form-data request.

2. Specify a Content-Type of the request that specifies that it multipart/form-data and what the boundary is.

3. Create body of request, separating the individual components (each of the posted values as well as between each upload).

For more detail, see RFC 7578. Anyway, in Swift 3 and later, this might look like:

/// Create request
///
/// - parameter userid:   The userid to be passed to web service
/// - parameter password: The password to be passed to web service
/// - parameter email:    The email address to be passed to web service
///
/// - returns:            The `URLRequest` that was created


func createRequest(userid: String, password: String, email: String) throws -> URLRequest {
let parameters = [
"user_id"  : userid,
"email"    : email,
"password" : password]  // build your dictionary however appropriate
    

let boundary = generateBoundaryString()
    

let url = URL(string: "https://example.com/imageupload.php")!
var request = URLRequest(url: url)
request.httpMethod = "POST"
request.setValue("multipart/form-data; boundary=\(boundary)", forHTTPHeaderField: "Content-Type")
    

let fileURL = Bundle.main.url(forResource: "image1", withExtension: "png")!
request.httpBody = try createBody(with: parameters, filePathKey: "file", urls: [fileURL], boundary: boundary)
    

return request
}


/// Create body of the `multipart/form-data` request
///
/// - parameter parameters:   The optional dictionary containing keys and values to be passed to web service.
/// - parameter filePathKey:  The optional field name to be used when uploading files. If you supply paths, you must supply filePathKey, too.
/// - parameter urls:         The optional array of file URLs of the files to be uploaded.
/// - parameter boundary:     The `multipart/form-data` boundary.
///
/// - returns:                The `Data` of the body of the request.


private func createBody(with parameters: [String: String]? = nil, filePathKey: String, urls: [URL], boundary: String) throws -> Data {
var body = Data()
    

parameters?.forEach { (key, value) in
body.append("--\(boundary)\r\n")
body.append("Content-Disposition: form-data; name=\"\(key)\"\r\n\r\n")
body.append("\(value)\r\n")
}
    

for url in urls {
let filename = url.lastPathComponent
let data = try Data(contentsOf: url)
        

body.append("--\(boundary)\r\n")
body.append("Content-Disposition: form-data; name=\"\(filePathKey)\"; filename=\"\(filename)\"\r\n")
body.append("Content-Type: \(url.mimeType)\r\n\r\n")
body.append(data)
body.append("\r\n")
}
    

body.append("--\(boundary)--\r\n")
return body
}


/// Create boundary string for multipart/form-data request
///
/// - returns:            The boundary string that consists of "Boundary-" followed by a UUID string.


private func generateBoundaryString() -> String {
return "Boundary-\(UUID().uuidString)"
}

With:

extension URL {
/// Mime type for the URL
///
/// Requires `import UniformTypeIdentifiers` for iOS 14 solution.
/// Requires `import MobileCoreServices` for pre-iOS 14 solution


var mimeType: String {
if #available(iOS 14.0, *) {
return UTType(filenameExtension: pathExtension)?.preferredMIMEType ?? "application/octet-stream"
} else {
guard
let identifier = UTTypeCreatePreferredIdentifierForTag(kUTTagClassFilenameExtension, pathExtension as CFString, nil)?.takeRetainedValue(),
let mimeType = UTTypeCopyPreferredTagWithClass(identifier, kUTTagClassMIMEType)?.takeRetainedValue() as String?
else {
return "application/octet-stream"
}


return mimeType
}
}
}


extension Data {
    

/// Append string to Data
///
/// Rather than littering my code with calls to `data(using: .utf8)` to convert `String` values to `Data`, this wraps it in a nice convenient little extension to Data. This defaults to converting using UTF-8.
///
/// - parameter string:       The string to be added to the `Data`.
    

mutating func append(_ string: String, using encoding: String.Encoding = .utf8) {
if let data = string.data(using: encoding) {
append(data)
}
}
}

Having all of this, you now need to submit this request. I would advise this is done asynchronously. For example, using URLSession, you would do something like:

let request: URLRequest


do {
request = try createRequest(userid: userid, password: password, email: email)
} catch {
print(error)
return
}


let task = URLSession.shared.dataTask(with: request) { data, response, error in
guard let data = data, error == nil else {
// handle error here
print(error ?? "Unknown error")
return
}
    

// parse `data` here, then parse it
    

// note, if you want to update the UI, make sure to dispatch that to the main queue, e.g.:
//
// DispatchQueue.main.async {
//     // update your UI and model objects here
// }
}
task.resume()

If you are uploading large assets (e.g. videos or the like), you might want to use a file-based permutation of the above. See https://stackoverflow.com/a/70552269/1271826.

For Swift 2 renditions, see previous revision of this answer.

AlamoFire now supports Multipart:

https://github.com/Alamofire/Alamofire#uploading-multipartformdata

Here's a blog post with sample project that touches on using Multipart with AlamoFire.

http://www.thorntech.com/2015/07/4-essential-swift-networking-tools-for-working-with-rest-apis/

The relevant code might look something like this (assuming you're using AlamoFire and SwiftyJSON):

func createMultipart(image: UIImage, callback: Bool -> Void){
// use SwiftyJSON to convert a dictionary to JSON
var parameterJSON = JSON([
"id_user": "test"
])
// JSON stringify
let parameterString = parameterJSON.rawString(encoding: NSUTF8StringEncoding, options: nil)
let jsonParameterData = parameterString!.dataUsingEncoding(NSUTF8StringEncoding, allowLossyConversion: true)
// convert image to binary
let imageData = UIImageJPEGRepresentation(image, 0.7)
// upload is part of AlamoFire
upload(
.POST,
URLString: "http://httpbin.org/post",
multipartFormData: { multipartFormData in
// fileData: puts it in "files"
multipartFormData.appendBodyPart(fileData: jsonParameterData!, name: "goesIntoFile", fileName: "json.txt", mimeType: "application/json")
multipartFormData.appendBodyPart(fileData: imageData, name: "file", fileName: "iosFile.jpg", mimeType: "image/jpg")
// data: puts it in "form"
multipartFormData.appendBodyPart(data: jsonParameterData!, name: "goesIntoForm")
},
encodingCompletion: { encodingResult in
switch encodingResult {
case .Success(let upload, _, _):
upload.responseJSON { request, response, data, error in
let json = JSON(data!)
println("json:: \(json)")
callback(true)
}
case .Failure(let encodingError):
callback(false)
}
}
)
}


let fotoImage = UIImage(named: "foto")
createMultipart(fotoImage!, callback: { success in
if success { }
})

Thank you @Rob, your code is working fine, but in my case, I am retriving image from gallary and taking name of the image by using code:

let filename = url.lastPathComponent

But this code, displaying image extension as .JPG (in capital letter), but server not accepting extensions in captital letter, so i changed my code as:

 let filename =  (path.lastPathComponent as NSString).lowercaseString

and now my code is working fine.

Thank you :)