Angular Image上传到PHP并保存到上传文件夹

Question

我正在尝试通过有角度的httpClient发布方法将单个图像上传到我的php文件中，然后保存到上传文件夹中，但是我无法获取确切的错误，请提供帮助。

HTML和ANGULAR：

<input id="imagePath" type="file" class="input" name="imagePath" (change)="onFileSelect($event)" formControlName="imagePath"/>

Logic: 
selectedImage : File;

onFileSelect(event){
    this.selectedImage = <File>event.target.files[0];
}

// call http on submit form
onAddImage(){
  const fd = new FormData();
  fd.append('myFile', this.selectedImage, this.selectedImage.name);

  return this.httpClient.post(
    'http://localhost/api/upload.php', 
    newCard,
    {
      reportProgress: true,
      observe: 'events',
      headers: new HttpHeaders().set('Content-Type', [])
    }
  )
  .subscribe(
    res => console.log(res)
  );
}

PHP - server script:
$target_dir = "upload/";
$target_file = $target_dir . basename($_FILES["myFile"]["name"]);
$uploadOk = 1;
$imageFileType = strtolower(pathinfo($target_file,PATHINFO_EXTENSION));
// Check if image file is a actual image or fake image
if(isset($_POST["submit"])) {
    $check = getimagesize($_FILES["myFile"]["tmp_name"]);
    if($check !== false) {
        echo "File is an image - " . $check["mime"] . ".";
        $uploadOk = 1;
    } else {
        echo "File is not an image.";
        $uploadOk = 0;
    }
}

这是我的设置，似乎没有任何事情发生，当我登录.log时，登录名中什么都可以获取我选择的文件（图像）。