Usage details of curlopt_postfields parameter of php curl

When using curl to send some data to the server without paying attention to details, you may get the following results, which Not the ideal result:

But if you use http_build_query($post_data) instead When $post_data submits data to this php script, you will get different results from the above. This is the ideal result:

As can be seen from the above example, when using curl and the parameter is data, when submitting data to the server, http The header will send content_type: application/x-www-form-urlencoded. This is the header sent by the browser when submitting a form on a normal web page. And multipart/form-data knows that this is the form used to upload files. Including the boundary delimiter will add many bytes.