JavaScript - create a file out of json object and use it in a FormData

问题

I'm trying to simulate a file upload by providing file content instead of serving the real file.

So - I'm doing something like this:

 uploadFile(jsonContent: string, otherParams: string) {

const formData = new FormData();
formData.append('jsonContent', data, 'fileName.json');
formData.append('deal_id', dealId);

return this.http.post(this.base_url + '/files', formData);}

I'm not seeing the content being sent to the API. Any advice? What I'm doing wrong?

回答1:

Well, I've found a solution for this. In typescript you can create new File() and pass a blob object into it.

Now u can actually create a file in your client side and send it as part as your FormData.

here is the code:

    const st = JSON.stringify(json);

    const blob = new Blob([st], { type: 'application/json' });

    const file = new File([ blob ], 'FileName.json');

    const formData = new FormData();
    formData.append('file', file, 'FileName.json');
    formData.append('deal_id', dealId);

回答2:

Try to add this in your headers

const headers = {
  processData: false,
  contentType: false 
}

this.http.post(this.base_url + '/files', formData, headers)

来源：https://stackoverflow.com/questions/50784370/javascript-create-a-file-out-of-json-object-and-use-it-in-a-formdata