Swift 使用 Alamorefire 5 與 ASP.NET Core 3 Web API 合作影像上傳作業

記錄使用 ASP.NET Core 3 Web API 與 Alamorefire 5 合作上傳 UIImage 作業的順序。

ASP.NET Core 3 Web API 部分。新增一個 UploadApiController 負責上傳作業。只放一個 Action

[Route(“api/[controller]”)]
[ApiController]
public class UploadApiController : ControllerBase
{
   [HttpPost(“UploadImage”)]
   public async Task<string> UploadFile([FromForm] IFormFile file)
   {
      string uniqueFileName = null;
      
      if ( file != null)
      {
         try{
            string uploadsFolder = 
Path.Combine( Directory.GetCurrentDirectory(),”wwwroot", "file path" );
            uniqueFileName = DateTime.Now.ToString(“yyyyMMddHHmmssf”) + ".jpg";
            string filePath = Path.Combine(uploadsFolder, uniqueFileName);
            using (var fileStream = new FileStream(filePath, FileMode.Create))
            {
               await file.CopyToAsync(fileStream);
            }
            return $"img/{ uniqueFileName }";
         }
         catch(Exception ex){
            return ex.Message;
         }
      }
      else{
         return $”file is null.”;
      }
   }
}

在 Swift 檔案內，直接呼叫 Alamorefire

override func viewDidLoad() {
   super.viewDidLoad()
   // load image to UIImage object
   let image : UIImage = UIImage.init(named: “rocket.jpg”)!
   // call function to upload image
   postImage(image: image, parameters: [“platform” : “iOS”])
}
func postImage(image : UIImage, parameters : Dictionary<String, String>){
   // add headers
   let headers: HTTPHeaders = [
      “Content-type”: “multipart/form-data”
   ]
   // use Alamofire to upload file
   AF.upload( multipartFormData: {
      formData
      in
      // append parameters
      for (key, value) in parameters {
         formData.append( value.data(using: String.Encoding.utf8)!, withName: key)
      }
      // append data
      formData.append(
         image.jpegData(compressionQuality: 0.8)!
         , withName: “file” // note : asp.net core 3 need a parameter name to naming binary data
         , fileName: “file.jpeg”
         , mimeType: “image/jpeg”)
      },
      to: “https://website url/api/UploadApi/UploadImage",
      method: .post ,
      headers: headers)
      
      .response
      {
         response
         in
         let message : String = String( decoding: response.data!, as: UTF8.self)
         print(message)
      }
}