formData不起作用，追加后，我得到了空的表单数据

Question

我正在尝试使用以下代码发送formData，但是当我控制台formData时，我得到的是空的formData

我是初学者，我真的很困惑为什么会发生这种情况，请告诉我为什么我遇到问题可以帮助我一个人

我在这里记录formdata FormData {}

代码：

  onSubmit () {
        const formData = new FormData();
        formData.append('title', this.blogForm.get('title').value);
        formData.append('description', this.blogForm.get('description').value);
        formData.append('is_featured', this.blogForm.get('is_featured').value);
        formData.append('is_active', this.blogForm.get('is_active').value);
        formData.append('image', this.blogForm.get('image').value);

    console.log(formData);

     this.blogService.createBlog(formData).subscribe(
            res => {
              if (!res) {
                this.uploadError = "Error occured";
              } else {
                this.router.navigate(['/admin/blogs']);
              }
            },
            error => this.error = error
          );

    createBlog(blog) {
        return this.http.post<Blog>(this.serverUrl + 'admin-blog-list', blog)
          .pipe(
            catchError(this.handleError)
          );
      }

Answer 1

由于 formData 是一个对象，因此要访问其值，必须使用

console.log(formData.get('title'))

for (var key of formData.keys()) {
 console.log(key); 
}

for (var value of formData.values()) {
 console.log(value); 
}

请参阅https://developer.mozilla.org/en-US/docs/Web/API/FormData/FormData

Answer 2

嗨，嗨，我不确定您是否会获得this.blogForm.get（*）。value，但是如果获得您的价值，请立即尝试解决问题

onSubmit () {

           //Change this of code 

            let formdata: FormData = new FormData();

            formData.append('title', this.blogForm.get('title').value);
            formData.append('description', this.blogForm.get('description').value);
            formData.append('is_featured', this.blogForm.get('is_featured').value);
            formData.append('is_active', this.blogForm.get('is_active').value);
            formData.append('image', this.blogForm.get('image').value);

        console.log(formData);

         this.blogService.createBlog(formData).subscribe(
                res => {
                  if (!res) {
                    this.uploadError = "Error occured";
                  } else {
                    this.router.navigate(['/admin/blogs']);
                  }
                },
                error => this.error = error
              );

        createBlog(blog) {
            return this.http.post<Blog>(this.serverUrl + 'admin-blog-list', blog)
              .pipe(
                catchError(this.handleError)
              );
          }

如果仍然无法正常工作，请告诉我