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How to bind selected option with the attribut in Svelte

I have a svelte component where i want to connect a selected input with a declared attribute.
My problem is that the binding of the selected value of status to the attribute'status' declared in 'flightschedules' doesnt work.
The options are from the attribute questions: on-time, delayed, cancelled
Can somebody help me please ?
Here is my code (its a component to create form, e.g create a flightschedule):
<script>
import axios from "axios";
import { onMount } from "svelte";
export let params = {};
let flightschedule = {
timeofdeparture: "",
flightnumber: "",
gatenumber: "",
status: "",
privatejetline_id: null,
};
let questions = [
{ text: "on-time" },
{ text: "delayed" },
{ text: "cancelled" },
];
let selected;
let privatejetline_ids = [];
onMount(() => {
getPrivateJetLineIds();
selected = params.status;
});
function getPrivateJetLineIds() {
axios
.get("http://localhost:8080/flights/privatejetline")
.then((response) => {
privatejetline_ids = [];
for (let privatejetline of response.data) {
privatejetline_ids.push(privatejetline.id);
}
flightschedule.privatejetline_id = privatejetline_ids[0];
});
}
function addFlightSchedule() {
axios
.post("http://localhost:8080/flights/flightschedule", flightschedule)
.then((response) => {
alert("Flight Schedule added");
console.log(response.data);
})
.catch((error) => {
console.log(error);
alert(error);
});
}
</script>
<div class="mb-3">
<label for="" class="form-label">Status</label>
<select bind:value={flightschedule.status} class="from-select">
<option value="" disabled>-- Select Status --</option>
{#each questions as question}
<option value={selected} selected={selected===flightschedule.status}>{question.text}</option>
{/each}
</select>
</div>

Actually, no need for selected variable, just bind the flightschedule.status. Try following in REPL.
<script>
let flightschedule = {
timeofdeparture: "",
flightnumber: "",
gatenumber: "",
status: "",
privatejetline_id: null,
};
let questions = [
{ text: "on-time" },
{ text: "delayed" },
{ text: "cancelled" },
];
$: console.log('---->', flightschedule.status)
</script>
<div class="mb-3">
<label for="" class="form-label">Status</label>
<select bind:value={flightschedule.status} class="from-select">
<option value="" disabled>-- Select Status --</option>
{#each questions as question}
<option value={question.text}>{question.text}</option>
{/each}
</select>
</div>

<option value={selected} this line can’t be right. You’re binding all three options to the same value.
You probably want following:
<select bind:value={selected} class="from-select">
<option value="" disabled>-- Select Status --</option>
{#each questions as question}
<option value={question.text}>{question.text}</option>
{/each}
</select>

How to iterate through array that is value of key in JSON

I have JSON file like this
[
{
"id": 1,
"country": "Afghanistan",
"city": ["Eshkashem","Fayzabad","Jurm","Khandud"]
},
{
"id": 2,
"country": "Italy",
"city": ["Milano","Rome","Torino","Venezia"]
}
]
and I want to iterate through array placed in the city. Idea is to have two selects, where the first select is reserved for countries and the second is reserved for cities. Whenever the user selects a country, I want to populate the second select with a list of cities. Problem is that I receive only one array of all cities for that country. Here is my code:
export default class DiffCountries extends Component {
constructor(props) {
super(props);
this.state = {
isLoading: true,
contacts: [],
selectedCountry: [],
selectedCity: []
}
}
onChangeHandler = (event) => {
const test = CountriesData[event.target.value - 1];
this.setState({
selectedCountry: test,
selectedCity: this.state.selectedCountry.city
})
console.log(this.state.selectedCity);
}
render() {
const { contacts } = this.state;
return (
<div>
<select name="" id="" onChange={this.onChangeHandler}>
{CountriesData.map(item => {
const { id, country } = item;
return <option key={id} value={id}>{country}</option>
})}
</select>
<select name="" id="">
{this.state.selectedCountry !== undefined ?
<option value="">{this.state.selectedCountry.city}</option> :
null
}
</select>
</div>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/16.6.3/umd/react.production.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react-dom/16.6.3/umd/react-dom.production.min.js"></script>
And here is the screenshot of my problem
Thank you in advance!

You need to use map() on the city array.
<select name = "" id = "" > {
this.state.selectedCountry !== undefined ?
this.state.selectedCountry.city.map((x,i) => <option value={x} key={i}>{x}</option>)
:null
}
</select>

You need to iterate through the array.
this.state.selectedCountry.city.map((city, index) => {
return <option value={city} key={index}>{city}</option>
})
Be aware, that using the index as a key is considered an anti pattern. You could use the name of the city as a key as well. E.g.:
this.state.selectedCountry.city.map(city => {
return <option value={city} key={city}>{city}</option>
})
edit to add link to mdn docs as suggested in comments: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/map

Example:
const CountriesData = [
{
id: 1,
country: 'Afghanistan',
city: ['Eshkashem', 'Fayzabad', 'Jurm', 'Khandud'],
},
{
id: 2,
country: 'Italy',
city: ['Milano', 'Rome', 'Torino', 'Venezia'],
},
];
class DiffCountries extends React.Component {
constructor(props) {
super(props);
this.state = {
selectedCountry: null,
};
}
onChangeHandler = event => {
const selectedCountry = CountriesData[event.target.value - 1];
this.setState({
selectedCountry,
});
};
render() {
const { selectedCountry } = this.state;
return (
<div>
<select
name="country"
defaultValue="country"
onChange={this.onChangeHandler}
>
<option disabled value="country">
Select country
</option>
{CountriesData.map(({ id, country }) => (
<option key={id} value={id}>
{country}
</option>
))}
</select>
{selectedCountry && (
<select name="city" defaultValue="city">
<option disabled value="city">
Select city
</option>
{selectedCountry.city.map(item => (
<option key={item} value={item}>
{item}
</option>
))}
</select>
)}
</div>
);
}
}
ReactDOM.render(<DiffCountries />, document.getElementById('container'));

How can I get text selected when category clicked on combobox ? (Vue.JS 2)

I have a vue component like this :
<script>
export default{
template: '\
<select class="form-control" v-model="selected" v-on:change="search">\
<option v-for="option in options" v-bind:value="option.id" v-bind:disabled="option.disabled">{{ option.name }}</option>\
</select>',
mounted() {
this.fetchList();
},
data() {
return {
selected: '',
options: [{id: '', name: window.trans.category.select}]
};
},
methods: {
search(e){
window.location = window.BaseUrl + '/search?q=&cat=' + e.target.value;
},
fetchList: function() {
this.$http.post(window.BaseUrl+'/category/list?parent_id=all').then(function (response) {
response.data.forEach(function(item){
this.options.push({id:item.id, name:item.name})
}, this);
});
},
}
};
</script>
When category clicked, I want get text of the category
On my code above, I use this : e.target.value to get id selected and it works
But, how can I get text selected when category clicked?
I try this : e.target.text, but id does not work
Is there anyone who can help me?

Given you want both id and name, you can try this:
template: '\
<select class="form-control" v-on:change="search">\
<option v-for="option in options" v-bind:value="option.id" #click="selected=option.name" v-bind:disabled="option.disabled">{{ option.name }}</option>\
</select>',
mounted() {
this.fetchList();
},

Display a default value in HTML select using Vue.js and Minimalect

I'm using Vue.js with the Mininmalect HTML select plugin to display a list of countries by name and value (value being the 2 digit country code).
I've got it to work when using the plugin to select a country. It's adds the value to the selected state.
What I can't work out is how display a value/country when there is already one in state (i.e. from the database when the page loads).
This is what I have:
<template>
<select name="country" v-model="country">
<option v-for="country in countries" value="{{ country.value }}">{{ country.label }}</option>
</select>
</template>
<script>
export default {
data() {
return {
selected: 'GB',
countries: require('../utilities/countries.js'),
}
},
ready() {
var vm = this;
$('select').minimalect({
onchange: function(value) {
vm.selected = value;
}
});
}
};
</script>
I'm struggling to get the select attribute to appear, i.e. <option value="GB" selected>United Kingdom</option> so there is a default when the page is loaded.

You've got v-model="country", so if you just set the value of country to the database value, the select will automatically be set to that value.
data() {
return {
country: 'GB',
countries: require('../utilities/countries.js'),
}
},
ready() {
var vm = this;
$('select').minimalect({
onchange: function(value) {
vm.country = value;
},
afterinit: function() {
$('select').val(vm.country).change();
}
});
}

Change your v-model with selected. And I think your problem is a performance problem. Add a setTimeout for your function.
<template>
<select name="country" v-model="selected">
<option v-for="country in countries" value="{{ country.value }}">{{ country.label }}</option>
</select>
</template>
<script>
export default {
data() {
return {
selected: 'GB',
countries: require('../utilities/countries.js'),
}
},
ready() {
var vm = this;
setTimeout(function(){
$('select').minimalect({
onchange: function(value) {
vm.selected = value;
}
});
});
}
};
</script>

vue js how to set option value selected

I'm using vue js for my application in select option input..I need to set default value should be selected in the drop down and while on change i would like to call two functions ..
I'm new to vue js..
My Code :
var listingVue = new Vue({
el: '#mountain',
data:{
formVariables: {
country_id: '',
mountain_id: '',
peak_id: ''
},
countrylist:[],
mountainlist:[],
},
ready: function() {
var datas = this.formVariables;
this.getCountry();
},
methods: {
getCountry: function()
{
this.$http.get(baseurl+'/api/v1/device/getCountry',function(response)
{
this.$set('countrylist',response.result);
//alert(jQuery('#country_id').val());
});
},
getMountain: function(country_id)
{
var datas = this.formVariables;
datas.$set('country_id', jQuery('#country_id').val() );
postparemeters = {country_id:datas.country_id};
this.$http.post(baseurl+'/api/v1/site/getMountain',postparemeters,function(response)
{
if(response.result)
this.$set('mountainlist',response.result);
else
this.$set('mountainlist','');
});
},
});
<select
class="breadcrumb_mountain_property"
id="country_id"
v-model="formVariables.country_id"
v-on="change:getMountain(formVariables.country_id);">
<option
v-repeat = "country: countrylist"
value="#{{country.id}}" >
#{{country.name}}
</option>
</select>

With vue 2, the provided answer won't work that well. I had the same problem and the vue documentation isn't that clear concerning <select>. The only way I found for <select> tags to work properly, was this (when talking of the question):
<select v-model="formVariables.country_id">
<option v-for = "country in countrylist" :value="country.id" >{{country.name}}</option>
</select>
I assume, that the #-sign in #{{...}} was due to blade, it should not be necessary when not using blade.

In VueJS 2 you can bind selected to the default value you want. For example:
<select
class="breadcrumb_mountain_property"
id="country_id"
v-model="formVariables.country_id"
v-on:change="getMountain(formVariables.country_id);">
<option
v-for = "country in countrylist"
:selected="country.id == 1"
:value="country.id" >
{{country.name}}
</option>
</select>
So, during the iteration of the countryList, the country with the id 1 will be selected because country.id == 1 will be true which means selected="true".
UPDATED:
As Mikee suggested, instead of v-on="change:getMountain(formVariables.country_id);" there is a new way to for binding events. There is also a short form #change="getMountain(formVariables.country_id);"

You should use the 'options' attribute in place of trying to v-repeat <option></option>:
VM
data: {
countryList: [
{ text:'United States',value:'US' },
{ text:'Canada',value:'CA' }
]
},
watch: {
'formVariables.country_id': function() {
// do any number of things on 'change'
}
}
HTML
<select
class="breadcrumb_mountain_property"
id="country_id"
v-model="formVariables.country_id"
options="countryList">
</select>

You can use select in this way. Remember to use array in v-for.
<select v-model="album.primary_artist">
<option v-for="i in artistList" :key="i.id" :value="i.name">
{{ i.name }}
</option>
</select>

You can use this way.
<select v-model="userData.categoryId" class="input mb-3">
<option disabled value="null">Kategori</option>
<option
v-for="category in categoryList"
:key="category.id"
:value="category.id"
>
{{ category.name }}
</option>
</select>
export default {
data() {
return {
categoryList: [],
userData: {
title: null,
categoryId: null,
},
};
},
The important thing here is what the categoryId value is, the default option value should be that.
categoryId: null,
<option disabled value="null">Kategori</option>
Here we use categoryId as value in v-model and initialize it with null. Value must be null in default option.
<select v-model="userData.categoryId" class="input mb-3">