CODE EXAMPLE FOR SWIFT

swift alamofire x-www-form-urlencoded

let parameters: [String: [String]] = [
    "foo": ["bar"],
    "baz": ["a", "b"],
    "qux": ["x", "y", "z"]
]

// All three of these calls are equivalent
AF.request("https://httpbin.org/post", method: .post, parameters: parameters)
AF.request("https://httpbin.org/post", method: .post, parameters: parameters, encoder: URLEncodedFormParameterEncoder.default)
AF.request("https://httpbin.org/post", method: .post, parameters: parameters, encoder: URLEncodedFormParameterEncoder(destination: .httpBody))

// HTTP body: "qux[]=x&qux[]=y&qux[]=z&baz[]=a&baz[]=b&foo[]=bar"