如何在Swift 5中发送带有httpBody表单数据的POST请求？

import Foundation

func sendPostRequest() {
    // 创建URL对象
    guard let url = URL(string: "https://example.com/api") else {
        print("Invalid URL")
        return
    }
    
    // 创建请求对象
    var request = URLRequest(url: url)
    request.httpMethod = "POST"
    
    // 设置请求头
    request.setValue("application/x-www-form-urlencoded", forHTTPHeaderField: "Content-Type")
    
    // 设置请求体数据
    let formData = "username=test&password=123456"
    request.httpBody = formData.data(using: .utf8)
    
    // 创建URLSession对象
    let session = URLSession.shared
    
    // 发送请求
    let task = session.dataTask(with: request) { (data, response, error) in
        if let error = error {
            print("Error: \(error.localizedDescription)")
            return
        }
        
        if let data = data {
            // 处理返回的数据
            let result = String(data: data, encoding: .utf8)
            print("Response: \(result ?? "")")
        }
    }
    
    task.resume()
}

sendPostRequest()