Mixing
I don't understand the error: this.state.categories.map is not a function ReactJS
I'm fairly new to React JS and I'm getting the error that I can't use the map function on a state array i'm using.
I'm currently building a webapp using the Eventbrite api, getting data from the api is not the problem. But when I want to loop through the given data React responds with the error I have given above.
import React, { Component } from 'react'
import axios from 'axios'
export default class Categories extends Component {
state={
apiUrl : 'https://www.eventbriteapi.com/v3/categories/103',
OAuthToken : 'my OAuthToken',
loading: true,
categories:
}
componentWillMount(){
axios.get(`${this.state.apiUrl}?token=${this.state.OAuthToken}`)
.then(res => {
let result = res.data;
this.setState({categories : result});
console.log(this.state.categories);
if(this.state.result !== ''){
this.setState({loading:false});
}
})
.catch((error)=>{
console.log(error);
})
}
renderCategories(){
if(this.state.loading === false){
return(
<ul>
{this.state.categories.map(item=> (
<li key={item}>{item}</li>
))}
</ul>
)
}
}
render() {
return (
<div>
{this.renderCategories()}
</div>
)
}
}
I'm a little confused in what I'm doing wrong, any ideas?
javascript reactjs
asked Jan 2 at 23:42
Joey DeckersJoey Deckers
1
add a comment |
I'm fairly new to React JS and I'm getting the error that I can't use the map function on a state array i'm using.
I'm currently building a webapp using the Eventbrite api, getting data from the api is not the problem. But when I want to loop through the given data React responds with the error I have given above.
import React, { Component } from 'react'
import axios from 'axios'
export default class Categories extends Component {
state={
apiUrl : 'https://www.eventbriteapi.com/v3/categories/103',
OAuthToken : 'my OAuthToken',
loading: true,
categories:
}
componentWillMount(){
axios.get(`${this.state.apiUrl}?token=${this.state.OAuthToken}`)
.then(res => {
let result = res.data;
this.setState({categories : result});
console.log(this.state.categories);
if(this.state.result !== ''){
this.setState({loading:false});
}
})
.catch((error)=>{
console.log(error);
})
}
renderCategories(){
if(this.state.loading === false){
return(
<ul>
{this.state.categories.map(item=> (
<li key={item}>{item}</li>
))}
</ul>
)
}
}
render() {
return (
<div>
{this.renderCategories()}
</div>
)
}
}
I'm a little confused in what I'm doing wrong, any ideas?
javascript reactjs
asked Jan 2 at 23:42
Joey DeckersJoey Deckers
1
Are you sure thatresultcoming back from your network call is actually an array?
– Matthew Herbst
Jan 2 at 23:47
What does theconsole.log()tell you about the updated value of thecategoriesproperty?
– Pointy
Jan 2 at 23:47
res.datais possibly not an array?
– Emile Bergeron
Jan 2 at 23:47
Ah the problem was that it isn't an array. Stupid me got clumsy. Thanks for the assistance!
– Joey Deckers
Jan 3 at 0:18
add a comment |
I'm fairly new to React JS and I'm getting the error that I can't use the map function on a state array i'm using.
I'm currently building a webapp using the Eventbrite api, getting data from the api is not the problem. But when I want to loop through the given data React responds with the error I have given above.
import React, { Component } from 'react'
import axios from 'axios'
export default class Categories extends Component {
state={
apiUrl : 'https://www.eventbriteapi.com/v3/categories/103',
OAuthToken : 'my OAuthToken',
loading: true,
categories:
}
componentWillMount(){
axios.get(`${this.state.apiUrl}?token=${this.state.OAuthToken}`)
.then(res => {
let result = res.data;
this.setState({categories : result});
console.log(this.state.categories);
if(this.state.result !== ''){
this.setState({loading:false});
}
})
.catch((error)=>{
console.log(error);
})
}
renderCategories(){
if(this.state.loading === false){
return(
<ul>
{this.state.categories.map(item=> (
<li key={item}>{item}</li>
))}
</ul>
)
}
}
render() {
return (
<div>
{this.renderCategories()}
</div>
)
}
}
I'm a little confused in what I'm doing wrong, any ideas?
javascript reactjs
asked Jan 2 at 23:42
Joey DeckersJoey Deckers
1
I'm fairly new to React JS and I'm getting the error that I can't use the map function on a state array i'm using.
I'm currently building a webapp using the Eventbrite api, getting data from the api is not the problem. But when I want to loop through the given data React responds with the error I have given above.
import React, { Component } from 'react'
import axios from 'axios'
export default class Categories extends Component {
state={
apiUrl : 'https://www.eventbriteapi.com/v3/categories/103',
OAuthToken : 'my OAuthToken',
loading: true,
categories:
}
componentWillMount(){
axios.get(`${this.state.apiUrl}?token=${this.state.OAuthToken}`)
.then(res => {
let result = res.data;
this.setState({categories : result});
console.log(this.state.categories);
if(this.state.result !== ''){
this.setState({loading:false});
}
})
.catch((error)=>{
console.log(error);
})
}
renderCategories(){
if(this.state.loading === false){
return(
<ul>
{this.state.categories.map(item=> (
<li key={item}>{item}</li>
))}
</ul>
)
}
}
render() {
return (
<div>
{this.renderCategories()}
</div>
)
}
}
I'm a little confused in what I'm doing wrong, any ideas?
javascript reactjs
javascript reactjs
asked Jan 2 at 23:42
Joey DeckersJoey Deckers
1
asked Jan 2 at 23:42
Joey DeckersJoey Deckers
1
asked Jan 2 at 23:42
Joey DeckersJoey Deckers
1
asked Jan 2 at 23:42
Joey DeckersJoey Deckers
1
asked Jan 2 at 23:42
Joey DeckersJoey Deckers
1
1
Are you sure thatresultcoming back from your network call is actually an array?
– Matthew Herbst
Jan 2 at 23:47
What does theconsole.log()tell you about the updated value of thecategoriesproperty?
– Pointy
Jan 2 at 23:47
res.datais possibly not an array?
– Emile Bergeron
Jan 2 at 23:47
Ah the problem was that it isn't an array. Stupid me got clumsy. Thanks for the assistance!
– Joey Deckers
Jan 3 at 0:18
add a comment |
Are you sure thatresultcoming back from your network call is actually an array?
– Matthew Herbst
Jan 2 at 23:47
What does theconsole.log()tell you about the updated value of thecategoriesproperty?
– Pointy
Jan 2 at 23:47
res.datais possibly not an array?
– Emile Bergeron
Jan 2 at 23:47
Ah the problem was that it isn't an array. Stupid me got clumsy. Thanks for the assistance!
– Joey Deckers
Jan 3 at 0:18
Are you sure that
result coming back from your network call is actually an array?– Matthew Herbst
Jan 2 at 23:47
Are you sure that
result coming back from your network call is actually an array?– Matthew Herbst
Jan 2 at 23:47
What does the
console.log() tell you about the updated value of the categories property?– Pointy
Jan 2 at 23:47
What does the
console.log() tell you about the updated value of the categories property?– Pointy
Jan 2 at 23:47
res.data is possibly not an array?– Emile Bergeron
Jan 2 at 23:47
res.data is possibly not an array?– Emile Bergeron
Jan 2 at 23:47
Ah the problem was that it isn't an array. Stupid me got clumsy. Thanks for the assistance!
– Joey Deckers
Jan 3 at 0:18
Ah the problem was that it isn't an array. Stupid me got clumsy. Thanks for the assistance!
– Joey Deckers
Jan 3 at 0:18
add a comment |
2 Answers
2
active
oldest
votes
The .map function only works on array-like variables. If that's the actual endpoint that you're calling then from the documentation it looks like it's not returning an array but an Object in the following format:
{
"id": "103",
"resource_uri": "https://www.eventbriteapi.com/v3/categories/103/",
"name": "Music",
"name_localized": "Music",
"short_name": "Music",
"short_name_localized": "Music",
"subcategories": [
{
"id": "3003",
"resource_uri": "https://www.eventbriteapi.com/v3/subcategories/3003/",
"name": "Classical",
"parent_category": {}
}
]
}
If you want to iterate through the keys or values you can turn that Object into an array using Object.keys(result) or Object.values(result)
answered Jan 3 at 0:22
dandan
846620
add a comment |
Here is how I do this with fetch()...
fetch('https://www.eventbriteapi.com/v3/organizers/{organizer_id}/events/?status=live&token=******')
.then(response => response.json())
.then(data => gatherData(data.events))
function gatherData(data) {
const options = data.map(item => `
<div id="event-contain">
<div class="event-left" style="width: 66%;">
<img src="${item.logo.url}">
<a href="${item.url}"><h5>${item.name.html}</h5></a><br/>
<p>${item.description.text}</p>
<a href="${item.url}"><button style="margin-bottom: 10px; padding: 15px;">Buy Tickets</button></a><br/><br/>
<div class="spacer" style="width: 100%; height: 30px; border-top: 1px solid #e4e4e4;"></div>
</div>
</div>
`).join('');
evdis.innerHTML = options;
}
It seems like you are missing a step in setting a variable to the JSON response. You should then be able to enter into the highest state of the JSON response ( aka events ) This will allow you to iterate through all of the events that you own using .map and display those events.
I hope this helps.
Best of luck!
answered Jan 8 at 16:00
Nathan TiniusNathan Tinius
1064
add a comment |
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2 Answers
2
active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
The .map function only works on array-like variables. If that's the actual endpoint that you're calling then from the documentation it looks like it's not returning an array but an Object in the following format:
{
"id": "103",
"resource_uri": "https://www.eventbriteapi.com/v3/categories/103/",
"name": "Music",
"name_localized": "Music",
"short_name": "Music",
"short_name_localized": "Music",
"subcategories": [
{
"id": "3003",
"resource_uri": "https://www.eventbriteapi.com/v3/subcategories/3003/",
"name": "Classical",
"parent_category": {}
}
]
}
If you want to iterate through the keys or values you can turn that Object into an array using Object.keys(result) or Object.values(result)
answered Jan 3 at 0:22
dandan
846620
add a comment |
The .map function only works on array-like variables. If that's the actual endpoint that you're calling then from the documentation it looks like it's not returning an array but an Object in the following format:
{
"id": "103",
"resource_uri": "https://www.eventbriteapi.com/v3/categories/103/",
"name": "Music",
"name_localized": "Music",
"short_name": "Music",
"short_name_localized": "Music",
"subcategories": [
{
"id": "3003",
"resource_uri": "https://www.eventbriteapi.com/v3/subcategories/3003/",
"name": "Classical",
"parent_category": {}
}
]
}
If you want to iterate through the keys or values you can turn that Object into an array using Object.keys(result) or Object.values(result)
answered Jan 3 at 0:22
dandan
846620
add a comment |
The .map function only works on array-like variables. If that's the actual endpoint that you're calling then from the documentation it looks like it's not returning an array but an Object in the following format:
{
"id": "103",
"resource_uri": "https://www.eventbriteapi.com/v3/categories/103/",
"name": "Music",
"name_localized": "Music",
"short_name": "Music",
"short_name_localized": "Music",
"subcategories": [
{
"id": "3003",
"resource_uri": "https://www.eventbriteapi.com/v3/subcategories/3003/",
"name": "Classical",
"parent_category": {}
}
]
}
If you want to iterate through the keys or values you can turn that Object into an array using Object.keys(result) or Object.values(result)
answered Jan 3 at 0:22
dandan
846620
The .map function only works on array-like variables. If that's the actual endpoint that you're calling then from the documentation it looks like it's not returning an array but an Object in the following format:
{
"id": "103",
"resource_uri": "https://www.eventbriteapi.com/v3/categories/103/",
"name": "Music",
"name_localized": "Music",
"short_name": "Music",
"short_name_localized": "Music",
"subcategories": [
{
"id": "3003",
"resource_uri": "https://www.eventbriteapi.com/v3/subcategories/3003/",
"name": "Classical",
"parent_category": {}
}
]
}
If you want to iterate through the keys or values you can turn that Object into an array using Object.keys(result) or Object.values(result)
answered Jan 3 at 0:22
dandan
846620
answered Jan 3 at 0:22
dandan
846620
answered Jan 3 at 0:22
dandan
846620
answered Jan 3 at 0:22
dandan
846620
846620
add a comment |
add a comment |
Here is how I do this with fetch()...
fetch('https://www.eventbriteapi.com/v3/organizers/{organizer_id}/events/?status=live&token=******')
.then(response => response.json())
.then(data => gatherData(data.events))
function gatherData(data) {
const options = data.map(item => `
<div id="event-contain">
<div class="event-left" style="width: 66%;">
<img src="${item.logo.url}">
<a href="${item.url}"><h5>${item.name.html}</h5></a><br/>
<p>${item.description.text}</p>
<a href="${item.url}"><button style="margin-bottom: 10px; padding: 15px;">Buy Tickets</button></a><br/><br/>
<div class="spacer" style="width: 100%; height: 30px; border-top: 1px solid #e4e4e4;"></div>
</div>
</div>
`).join('');
evdis.innerHTML = options;
}
It seems like you are missing a step in setting a variable to the JSON response. You should then be able to enter into the highest state of the JSON response ( aka events ) This will allow you to iterate through all of the events that you own using .map and display those events.
I hope this helps.
Best of luck!
answered Jan 8 at 16:00
Nathan TiniusNathan Tinius
1064
add a comment |
Here is how I do this with fetch()...
fetch('https://www.eventbriteapi.com/v3/organizers/{organizer_id}/events/?status=live&token=******')
.then(response => response.json())
.then(data => gatherData(data.events))
function gatherData(data) {
const options = data.map(item => `
<div id="event-contain">
<div class="event-left" style="width: 66%;">
<img src="${item.logo.url}">
<a href="${item.url}"><h5>${item.name.html}</h5></a><br/>
<p>${item.description.text}</p>
<a href="${item.url}"><button style="margin-bottom: 10px; padding: 15px;">Buy Tickets</button></a><br/><br/>
<div class="spacer" style="width: 100%; height: 30px; border-top: 1px solid #e4e4e4;"></div>
</div>
</div>
`).join('');
evdis.innerHTML = options;
}
It seems like you are missing a step in setting a variable to the JSON response. You should then be able to enter into the highest state of the JSON response ( aka events ) This will allow you to iterate through all of the events that you own using .map and display those events.
I hope this helps.
Best of luck!
answered Jan 8 at 16:00
Nathan TiniusNathan Tinius
1064
add a comment |
Here is how I do this with fetch()...
fetch('https://www.eventbriteapi.com/v3/organizers/{organizer_id}/events/?status=live&token=******')
.then(response => response.json())
.then(data => gatherData(data.events))
function gatherData(data) {
const options = data.map(item => `
<div id="event-contain">
<div class="event-left" style="width: 66%;">
<img src="${item.logo.url}">
<a href="${item.url}"><h5>${item.name.html}</h5></a><br/>
<p>${item.description.text}</p>
<a href="${item.url}"><button style="margin-bottom: 10px; padding: 15px;">Buy Tickets</button></a><br/><br/>
<div class="spacer" style="width: 100%; height: 30px; border-top: 1px solid #e4e4e4;"></div>
</div>
</div>
`).join('');
evdis.innerHTML = options;
}
It seems like you are missing a step in setting a variable to the JSON response. You should then be able to enter into the highest state of the JSON response ( aka events ) This will allow you to iterate through all of the events that you own using .map and display those events.
I hope this helps.
Best of luck!
answered Jan 8 at 16:00
Nathan TiniusNathan Tinius
1064
Here is how I do this with fetch()...
fetch('https://www.eventbriteapi.com/v3/organizers/{organizer_id}/events/?status=live&token=******')
.then(response => response.json())
.then(data => gatherData(data.events))
function gatherData(data) {
const options = data.map(item => `
<div id="event-contain">
<div class="event-left" style="width: 66%;">
<img src="${item.logo.url}">
<a href="${item.url}"><h5>${item.name.html}</h5></a><br/>
<p>${item.description.text}</p>
<a href="${item.url}"><button style="margin-bottom: 10px; padding: 15px;">Buy Tickets</button></a><br/><br/>
<div class="spacer" style="width: 100%; height: 30px; border-top: 1px solid #e4e4e4;"></div>
</div>
</div>
`).join('');
evdis.innerHTML = options;
}
It seems like you are missing a step in setting a variable to the JSON response. You should then be able to enter into the highest state of the JSON response ( aka events ) This will allow you to iterate through all of the events that you own using .map and display those events.
I hope this helps.
Best of luck!
answered Jan 8 at 16:00
Nathan TiniusNathan Tinius
1064
edited Jan 8 at 16:07
answered Jan 8 at 16:00
Nathan TiniusNathan Tinius
1064
answered Jan 8 at 16:00
Nathan TiniusNathan Tinius
1064
answered Jan 8 at 16:00
Nathan TiniusNathan Tinius
1064
1064
add a comment |
add a comment |
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Are you sure that
resultcoming back from your network call is actually an array?– Matthew Herbst
Jan 2 at 23:47
What does the
console.log()tell you about the updated value of thecategoriesproperty?– Pointy
Jan 2 at 23:47
res.datais possibly not an array?– Emile Bergeron
Jan 2 at 23:47
Ah the problem was that it isn't an array. Stupid me got clumsy. Thanks for the assistance!
– Joey Deckers
Jan 3 at 0:18