Check out example codes for "upload a single image alamofire 5.0 swift". It will help you in understanding the concepts better.

Code Example 1

headerFile()
   
    AF.upload(multipartFormData: { multipartFormData in
        
        for (key, value) in parameters {
            if let temp = value as? String {
                multipartFormData.append(temp.data(using: .utf8)!, withName: key)
            }
            if let temp = value as? Int {
                multipartFormData.append("\(temp)".data(using: .utf8)!, withName: key)
            }
            if let temp = value as? NSArray {
                temp.forEach({ element in
                    let keyObj = key + "[]"
                    if let string = element as? String {
                        multipartFormData.append(string.data(using: .utf8)!, withName: keyObj)
                    } else
                        if let num = element as? Int {
                            let value = "\(num)"
                            multipartFormData.append(value.data(using: .utf8)!, withName: keyObj)
                    }
                })
            }
        }
        
        if let data = imageData{
            multipartFormData.append(data, withName: "file", fileName: "\(Date.init().timeIntervalSince1970).png", mimeType: "image/png")
        }
    },
              to: endUrl, method: .post , headers: headers)
        .responseJSON(completionHandler: { (response) in
            
            print(response)
            
            if let err = response.error{
                print(err)
                onError?(err)
                return
            }
            print("Succesfully uploaded")
            
            let json = response.data
            
            if (json != nil)
            {
                let jsonObject = JSON(json!)
                print(jsonObject)
            }
        })
  }

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