使用Alamofire发送POST JSON对象时报错：Extra argument in call

Hey there! That "Extra argument in call" error pops up because you’re using syntax from an older Alamofire version (like 3.x or earlier) with a newer release of the framework. Alamofire overhauled its API starting from version 4.0, so let’s adjust your code to match the modern syntax.

What’s Wrong with the Original Code? #

• Uppercase method enums like .POST were replaced with lowercase variants (.post)
• encoding: .JSON was renamed to JSONEncoding.default
• The request method’s parameter order and naming shifted to be more consistent

Corrected Code for Alamofire 4.x+ #

Here’s the updated version that works with recent Alamofire releases:

import Alamofire

let parameters = [ "foo": [1,2,3], "bar": [ "baz": "qux" ] ]

// Use AF.request (or Alamofire.request) with modern syntax
AF.request("https://httpbin.org/post", 
           method: .post, 
           parameters: parameters, 
           encoding: JSONEncoding.default)
    .responseJSON { response in
        // Handle your response result here
        switch response.result {
        case .success(let responseData):
            print("Request succeeded: \(responseData)")
        case .failure(let error):
            print("Request failed: \(error.localizedDescription)")
        }
    }

Additional Notes #

• For Alamofire 5.x+, AF is the recommended shorthand alias (though Alamofire.request still works)
• JSONEncoding.default automatically sets the correct Content-Type: application/json header, so you don’t need to add it manually
• If you absolutely must stick with the old syntax (not recommended—old versions are unmaintained), specify an older Alamofire version in your Podfile:

  pod 'Alamofire', '~> 3.0'
  

内容的提问来源于stack exchange，提问作者Kamal Trivedi