How do I create the URL to send a GET request for a form?

Question

I am using this form.

<form action="http://localhost:3000/">
  <input type="text"
    id="url"
    name="url"
    v-model="url"
    placeholder="http://">

  <input type="text" id="message" name="message" value="888">
  <button @click="submit" :disabled="disabled">Go</button>
</form>

Until now, pressing a button resulted in http:localhost:300?url=...&message=... page being fetched.

Now I am trying to manually override this, so I added e.preventDefault(); to the submit() function. Now I can call Fetch API to fetch this URL manually, but how to I construct the URL from the form?

All online sources show how to do it with POST, no one seems to cover GET. Not sure why, because I need an idempotent request. Is there a standard way of doing this?

Answer 1

You're using Vue so typically you'd use something like this

<template>
  <form @submit.prevent="submit">
    <input
      type="text"
      v-model="url"
      placeholder="http://"
    />
    <input
      type="text"
      v-model="message"
    />
    <button type="submit" :disabled="disabled">Go</button>
  </form>
</template>

Notes:

• The <button> is a submit button without a click handler. This lets you listen for submit events on the <form> which can be triggered by mouse click or keyboard.
• The @submit.prevent handles the submit event on the <form> and prevents the default action automatically
• All <input> fields have an associated v-model backing a data property

Here's an example of the <script> part

const target = "http://localhost:3000/";

export default {
  data: () => ({
    url: "",
    message: "888",
  }),
  computed: {
    // just an example
    disabled: ({ url, message }) => url.length === 0 || message.length === 0,
  },
  methods: {
    async submit() {
      const params = new URLSearchParams({
        url: this.url,
        message: this.message
      });
      const res = await fetch(`${target}?${params}`);
    },
  },
};

---

In regular JS, you can still listen for submit events on the form, capture all the fields using FormData and turn that into a query string with URLSearchParams

document.querySelector("form").addEventListener("submit", async (e) => {
  e.preventDefault();
  const data = new FormData(e.target);
  const params = new URLSearchParams(data);
  const res = await fetch(`${e.target.action}?${params}`)
});