What is the best way to troubleshoot a quasar typescript file type error?

Currently, I am delving into Quasar using TypeScript and encountering a type error while working on file uploads.

Here is the snippet of my code where the type error arises specifically in the parameter of the form.append() method.

The error message reads as follows: "Argument of type 'Ref' is not assignable to parameter of type 'string | Blob'."

I am unsure about how to properly set the type for the file variable.

<script setup lang="ts">
import { ref, Ref } from 'vue';
import { QFile } from 'quasar';

const file: Ref<File | null> = ref(null);

const pickFile = (): void => {
  console.log(file.value);
  const formData = new FormData();
  formData.append('file', file);
  console.log(file.value);
};
</script>

<template>
  <q-file v-model="file" label="File Upload" @update:model-value="pickFile()">
    <template #prepend>
      <q-icon name="mdi-attachment"></q-icon>
    </template>
  </q-file>
</template>

https://i.stack.imgur.com/KhYjO.png

Answer №1

In FormData, the file is declared as either a String or Blob. This means that whatever you pass in must be of the same type. You can define your ref like this:

const fileData: Ref<String | Blob> = ref("");

Also, remember to only pass in the value when appending it to the form data, not the entire ref object.

formData.append("file", fileData.value);

I hope this explanation clears things up for you.

Answer №2

FormData only accepts either a Blob or a String. It seems you have declared the file variable as type null.

// Consider initializing file as an empty string instead.
const file: Ref<String | Blob> = ref("");

Similar questions

If you have not found the answer to your question or you are interested in this topic, then look at other similar questions below or use the search

Exploring Angular 4: Embracing the Power of Observables

I am currently working on a project that involves loading and selecting clients (not users, but more like customers). However, I have encountered an issue where I am unable to subscribe to the Observables being loaded in my component. Despite trying vario ...

Unable to assign a value to the HTMLInputElement's property: The input field can only be set to a filename or an empty string programmatically

When attempting to upload an image, I encountered the error message listed in the question title: This is my template <input type="file" formControlName="avatar" accept=".jpg, .jpeg .svg" #fileInput (change)="uploa ...

Is there a way for me to verify that the key of one object is a subset of the keys of another object?

export const masterKeysObject = { MAIN: 'main', REDIRECT: 'redirect', DASHBOARD: 'dashboard', USER_ID_PARAM: ':userId', CREATE_NEW: 'create_new' } as const; type MasterKeys = keyof type ...

execute the function once the filereader has completed reading the files

submitTCtoDB(updateTagForm:any){ for(let i=0;i<this.selectedFileList.length;i++){ let file=this.selectedFileList[i]; this.readFile(file, function(selectedFileList) { this.submitTC(updateTagForm,selectedFileList); }); } } } ...

What is the process of uploading a file from a Vue.js app to the local public disk in Laravel?

Hello there, I am looking to upload a file from a Vue.js app to the local public directory of Laravel and only store the unique name in MySQL upon form submission. However, I am unsure how to achieve this using JavaScript. // Template Tag <input type= ...

Failed to import due to an error from the downloaded dependency

I'm encountering an import error in the @react-three module of my downloaded package. ./node_modules/@react-three/drei/node_modules/troika-three-text/dist/troika-three-text.esm.js Attempted import error: 'webgl-sdf-generator' does not cont ...

Differences between Vue.js Composition API and Options API - utilizing posts ref within a v-for iteration

I am relatively new to working with VueJS, and I am facing a challenge that has me stumped. On a page that fetches data using axios from my posts on a wordpress site: export default { data() { return { postsUrl: "https://localhost/wordpre ...

example of reusing vue js component multiple times on a single page

Within my components, I am making an axios call. I have defined two of them with props that provide the URI for the axios call. export default { name: "CardData", props :['uri','suffixe' ,'label'], data : function (){ r ...

AngularJS2 brings a powerful and seamless implementation of indexedDB for efficient

I'm on the hunt for an indexeddb implementation that works seamlessly with Angularjs2. While I stumbled upon this api at https://github.com/gilf/angular2-indexeddb, it appears to be lacking in active development and may not be ready for production use ...

How to upgrade Angular Header/Http/RequestOptions from deprecated in Angular 6.0 to Angular 8.0?

When working on http requests in Angular 6.0, I typically follow this block of code. I attempted to incorporate the newer features introduced in Angular 8.0 such as HttpClient, HttpResponse, and HttpHeaders. However, I found that the syntax did not align ...

The frontend is not triggering the Patch API call

I am having trouble with my http.patch request not being called to the backend. This issue only occurs when I try calling it from the frontend. Oddly enough, when I tested it in Postman, everything worked perfectly. Testing the backend on its own shows t ...

The Ionic Menu fails to display on the screen

Today is my first foray into the world of Ionic App + VueJS development. As I navigate through my app, I encountered an issue with the ion-menu component that only shows up the first time I click on it. Let me give you an example: While in the Home compo ...

Guide to creating flexible routes with multiple changing parameters in Vue 3 using Vue Router

What is the best way to implement dynamic routes with multiple dynamic parameters in any order using Vue 3 and Vue Router? These parameters should be able to be passed in any order. In our web application, we have over 500 views which makes it impractic ...

Simultaneous Loading: Marvelous Vue Preloader Spinner and Content Display (Vuejs)

Is there a way to ensure that the preloader loads before displaying the content? I tried using the library from , but both the preloader and content load simultaneously. How can I make sure that the preloader loads first, followed by the content? Thank you ...

Exploring the use of national flag emojis in VS code

I've been attempting to use flag emojis as reactions on a Discord bot, but they just won't cooperate. Every time I try something like this > ':flag_jp:', I encounter the following error: Error: DiscordAPIError: Unknown Emoji EDIT ...

issue with the appearance of vue js transitions

Having some issues with Vue.js transitions. Works strangely in Chrome and not at all in Microsoft Edge. Hard to explain, so I've included a link to my code on JSFiddle for reference: link : my code /* animation*/ .slide-fade-enter-active, .slide-fade ...

How can I change a ReactNode into a text format?

I am looking for a way to convert the following code snippet into a string while preserving Tailwind CSS and other elements. My project uses Next.js with TypeScript and Tailwind CSS. Input : export default function Header_1() { return ( <div clas ...

The method getManyAndCount() in TypeORM does not include related data in its return result

I'm completely new to TypeORM and NestJs. Currently, I am working on a project where I have an entity called VehicleModel which has a ManyToOne relationship with VehicleBrand. However, when I execute getManyAndCount() on my query, I am puzzled as to ...

What is the best way to run a scheduled task automatically using node-cron?

I have a custom function that saves data to the database using the POST method. When testing it with Postman, I send an empty POST request to trigger the controller. Upon execution, the function triggers two more functions. One of them is responsible for ...

Tips for removing a row from a DataGrid column with the click of a button

I am facing a challenge with my data table that contains users. I am trying to implement a delete button for each row, but it seems like the traditional React approach may not work in this situation. Currently, I am utilizing the DataGrid component in the ...