upload file post request

  let finalFile
  $("#uploadAttachment").on('change', function(){
      let uploadedFile = $("#uploadAttachment").val();
      let userId = localStorage.getItem('userId');

      var formData = new FormData();
      formData.append("file", event.target.files[0]);
      formData.append("uid", userId);

      var file = this.files[0];
      var fileType = file["type"];
      var validImageTypes = ["image/gif", "image/jpeg", "image/png"];
      if ($.inArray(fileType, validImageTypes) < 0) {
           // invalid file type code goes here.
          errorBlock("#error_block","please select proper image file !");
              $("#uploadAttachment").val("");
      }
      else{
          $.post({
              url: api_url + "application/uploadFileForAuditionApplication",
              contentType: false,
              processData: false,
              enctype: 'multipart/form-data',
              data : formData,
              success : function(response) {
                  finalFile = response.payload;
              },
              error: function (error) {
                  console.log(error);
              }
          });
      }

  })