只需要将以下代码内容进行复制即可用到自己的程序/API接口中：

if(!empty($_POST['is_post']) && $_POST['is_post']==1){
    $url = "https://www.aoksend.com/index/api/send_email";
    $name = $_POST['name'];
    $email = $_POST['email'];
    $subject = $_POST['subject'];
    $message = $_POST['message'];
    if(empty($name)){
        echo json_encode(['message'=>'请填写Name','code' => 40001]);
        exit;
    }
    if(empty($email)){
        echo json_encode(['message'=>'请填写Email address','code' => 40002]);
        exit;
    }
    if(empty($subject)){
        echo json_encode(['message'=>'请填写Subject','code' => 40003]);
        exit;
    }
    if(empty($message)){
        echo json_encode(['message'=>'请填写Message','code' => 40004]);
        exit;
    }
    $time = date('Y-m-d H:i:s',time());
 
    $str = '{"username":"'.$name.'","contactemail":"'.$email.'","subject":"'.$subject.'","content":"'.$message.'","time":"'.$time.'"}';
 
    //app_key 注册Aoksend获取秘钥
    //to 需要接收提醒的邮箱
    //template_id Aoksend里的邮件模板ID
    $data = ['app_key'=>'cf6d0114ee5cd1e4800000005c20ac793', 'to'=>'test@Aoksend.com', 'template_id'=>'E_100008454408', 'data'=>$str];
 
    $curl = curl_init();
    curl_setopt($curl, CURLOPT_URL, $url);
    curl_setopt($curl, CURLOPT_SSL_VERIFYPEER, FALSE);
    curl_setopt($curl, CURLOPT_SSL_VERIFYHOST, FALSE);
    if (!empty($data)){
        curl_setopt($curl, CURLOPT_POST, 1);
        curl_setopt($curl, CURLOPT_POSTFIELDS, $data);
    }
    curl_setopt($curl, CURLOPT_RETURNTRANSFER, 1);
    $output = curl_exec($curl);
    curl_close($curl);
    echo $output;
    exit;
}
?>
联系表单
由AokSend支持邮件发送API
class="cf">
  <div class="half left cf">
    <input type="text" id="input-name" placeholder="Name">
    <input type="email" id="input-email" placeholder="Email address">
    <input type="text" id="input-subject" placeholder="Subject">
  div>
  <div class="half right cf">
    <textarea name="message" type="text" id="input-message" placeholder="Message">textarea>
  div>  
  <input type="submit" value="Submit" id="input-submit">
form>
<script>
  function submitForm() {
    // 阻止表单的默认提交行为
    event.preventDefault();
 
    // 假设你的表单数据在以下对象中
    var formData = {
      is_post: 1,
      name: document.getElementById('input-name').value,
      email: document.getElementById('input-email').value,
      subject: document.getElementById('input-subject').value,
      message: document.getElementById('input-message').value
    };
 
    // 将表单数据转换为查询字符串
    var queryString = Object.keys(formData).map(key => encodeURIComponent(key) + '=' + encodeURIComponent(formData[key])).join('&');
 
    // 初始化XMLHttpRequest对象
    var xhr = new XMLHttpRequest();
 
    // 设置请求类型、URL和异步
    xhr.open('POST', '', true);
 
    // 设置请求头（如果需要）
    xhr.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
 
    // 设置响应处理函数
    xhr.onreadystatechange = function () {
      if (xhr.readyState === 4 && xhr.status === 200) {
        // 请求成功完成
        var obj = JSON.parse(xhr.responseText);
        if(obj.code==200){
          //调用成功
          alert("提交成功，已发送邮件！")
        }else{
          alert(obj.message)
        }
      }
    };
    // 发送请求
    xhr.send(queryString);
  }
  document.getElementById('input-submit').addEventListener('click', submitForm);

github下载：GitHub - AokSend/Contact-Form-Submit-Send-Email

gitee下载：README.md · AokSend/Contact Form Submit Send Email - Gitee.com

欢迎各位有需要交流的朋友们留言互动