Javascript gets undefined on array
up vote
-1
down vote
favorite
I have the following data structure for javascript:
var data = {
"announcements": {
"IFT4S": [{
"id": "D7214",
"read_state": "unread",
"posted_at": "2018-10-25T14:35:54Z",
"title": "Reminder! Systems disruption: 27-28 Oct",
"message": "All University online systems will be unavailable."
}, {
"id": "B399C",
"read_state": "read",
"posted_at": "2018-10-22T09:04:48Z",
"title": "Stem Fair",
"message": "The STEM Careers Fair is taking place on 31 October 2018"
}, {
"id": "6F5EE",
"read_state": "unread",
"posted_at": "2018-10-22T09:04:48Z",
"title": "Smile more, worry less with our FREE course",
"message": "Take part in our Online Mindfulness Programme."
}]
}
}
I want to access the values of the keys "read_state", "posted_at", "title" and "message".
However, when I try data.announcements.IFT4S["title"] or any other key instead of "title" I get the undefined in the console.
What am I doing wrong?
javascript
edited Nov 8 at 16:50
Amy
21.1k1772131
asked Nov 8 at 16:46
Roman
31
add a comment |
up vote
-1
down vote
favorite
I have the following data structure for javascript:
var data = {
"announcements": {
"IFT4S": [{
"id": "D7214",
"read_state": "unread",
"posted_at": "2018-10-25T14:35:54Z",
"title": "Reminder! Systems disruption: 27-28 Oct",
"message": "All University online systems will be unavailable."
}, {
"id": "B399C",
"read_state": "read",
"posted_at": "2018-10-22T09:04:48Z",
"title": "Stem Fair",
"message": "The STEM Careers Fair is taking place on 31 October 2018"
}, {
"id": "6F5EE",
"read_state": "unread",
"posted_at": "2018-10-22T09:04:48Z",
"title": "Smile more, worry less with our FREE course",
"message": "Take part in our Online Mindfulness Programme."
}]
}
}
I want to access the values of the keys "read_state", "posted_at", "title" and "message".
However, when I try data.announcements.IFT4S["title"] or any other key instead of "title" I get the undefined in the console.
What am I doing wrong?
javascript
edited Nov 8 at 16:50
Amy
21.1k1772131
asked Nov 8 at 16:46
Roman
31
4
IFT4Sis an array. You will need to iterate over it to access objects. e.g.data.announcements.IFT4S[0]["title"]
– Nikhil Aggarwal
Nov 8 at 16:47
add a comment |
up vote
-1
down vote
favorite
up vote
-1
down vote
favorite
I have the following data structure for javascript:
var data = {
"announcements": {
"IFT4S": [{
"id": "D7214",
"read_state": "unread",
"posted_at": "2018-10-25T14:35:54Z",
"title": "Reminder! Systems disruption: 27-28 Oct",
"message": "All University online systems will be unavailable."
}, {
"id": "B399C",
"read_state": "read",
"posted_at": "2018-10-22T09:04:48Z",
"title": "Stem Fair",
"message": "The STEM Careers Fair is taking place on 31 October 2018"
}, {
"id": "6F5EE",
"read_state": "unread",
"posted_at": "2018-10-22T09:04:48Z",
"title": "Smile more, worry less with our FREE course",
"message": "Take part in our Online Mindfulness Programme."
}]
}
}
I want to access the values of the keys "read_state", "posted_at", "title" and "message".
However, when I try data.announcements.IFT4S["title"] or any other key instead of "title" I get the undefined in the console.
What am I doing wrong?
javascript
edited Nov 8 at 16:50
Amy
21.1k1772131
asked Nov 8 at 16:46
Roman
31
I have the following data structure for javascript:
var data = {
"announcements": {
"IFT4S": [{
"id": "D7214",
"read_state": "unread",
"posted_at": "2018-10-25T14:35:54Z",
"title": "Reminder! Systems disruption: 27-28 Oct",
"message": "All University online systems will be unavailable."
}, {
"id": "B399C",
"read_state": "read",
"posted_at": "2018-10-22T09:04:48Z",
"title": "Stem Fair",
"message": "The STEM Careers Fair is taking place on 31 October 2018"
}, {
"id": "6F5EE",
"read_state": "unread",
"posted_at": "2018-10-22T09:04:48Z",
"title": "Smile more, worry less with our FREE course",
"message": "Take part in our Online Mindfulness Programme."
}]
}
}
I want to access the values of the keys "read_state", "posted_at", "title" and "message".
However, when I try data.announcements.IFT4S["title"] or any other key instead of "title" I get the undefined in the console.
What am I doing wrong?
javascript
javascript
edited Nov 8 at 16:50
Amy
21.1k1772131
asked Nov 8 at 16:46
Roman
31
edited Nov 8 at 16:50
Amy
21.1k1772131
asked Nov 8 at 16:46
Roman
31
edited Nov 8 at 16:50
Amy
21.1k1772131
edited Nov 8 at 16:50
Amy
21.1k1772131
edited Nov 8 at 16:50
Amy
21.1k1772131
21.1k1772131
asked Nov 8 at 16:46
Roman
31
asked Nov 8 at 16:46
Roman
31
asked Nov 8 at 16:46
Roman
31
31
4
IFT4Sis an array. You will need to iterate over it to access objects. e.g.data.announcements.IFT4S[0]["title"]
– Nikhil Aggarwal
Nov 8 at 16:47
add a comment |
4
IFT4Sis an array. You will need to iterate over it to access objects. e.g.data.announcements.IFT4S[0]["title"]
– Nikhil Aggarwal
Nov 8 at 16:47
4
4
IFT4S is an array. You will need to iterate over it to access objects. e.g. data.announcements.IFT4S[0]["title"]– Nikhil Aggarwal
Nov 8 at 16:47
IFT4S is an array. You will need to iterate over it to access objects. e.g. data.announcements.IFT4S[0]["title"]– Nikhil Aggarwal
Nov 8 at 16:47
add a comment |
3 Answers
3
active
oldest
votes
up vote
0
down vote
accepted
IFT4S is an array, you can access its objects and their values values by calling:
data.announcements.IFT4S[index].title
with index beeing one of 0-2 here since the array contains 3 objects.
For example:
data.announcements.IFT4S[0].title
This is a very basic concept, check out any javascript guide to learn about arrays.
answered Nov 8 at 16:52
Evoxx
465
add a comment |
up vote
1
down vote
when I try data.announcements.IFT4S["title"] or any other key instead
of "title" I get the undefined in the console. What am I doing wrong?
What you are doing here is trying to access the title key of the IFT4S array.
The issue is that IFT4S doesn't have a title key. Instead, like an array object, it has indexes as keys.
IFT4S = [ {...}, {...}, {...} ]
To access the first element of the IFT4S array you would do it like this
IFT4S[0]
In your case that would return the object at the first position of IFT4S array (index 0)
{
id: "D7214",
read_state: "unread",
posted_at: "2018-10-25T14:35:54Z",
title: "Reminder! Systems disruption: 27-28 Oct",
message: "All University online systems will be unavailable."
}
If you want to get all the titles from all the elements inside IFT4S array you could do this
IFT4S.map(element => element.title)
Array.prototype.map returns a new array where each element is the result of applying the function specified inside map to each element of the original array.
In this case, it would return
[
"Reminder! Systems disruption: 27-28 Oct",
"Stem Fair",
"Smile more, worry less with our FREE course"
]
answered Nov 8 at 17:15
Joaquin Timerman
1245
add a comment |
up vote
1
down vote
You have to itrate over the array to get value from an array of object
var data = {
"announcements": {
"IFT4S": [
{
"id": "D7214",
"read_state": "unread",
"posted_at": "2018-10-25T14:35:54Z",
"title": "Reminder! Systems disruption: 27-28 Oct",
"message": "All University online systems will be unavailable."
},
{
"id": "B399C",
"read_state": "read",
"posted_at": "2018-10-22T09:04:48Z",
"title": "Stem Fair",
"message": "The STEM Careers Fair is taking place on 31 October 2018"
},
{
"id": "6F5EE",
"read_state": "unread",
"posted_at": "2018-10-22T09:04:48Z",
"title": "Smile more, worry less with our FREE course",
"message": "Take part in our Online Mindfulness Programme."
},
]
}
}
data.announcements.IFT4S.forEach(item => {
console.log(item.title)
})or you can do like this,
0 is the index
console.log(data.announcements.IFT4S[0].read_state)
console.log(data.announcements.IFT4S[0].title)answered Nov 8 at 16:53
Hafeez Hamza
307110
Nice. Might I suggest using item.title in your working example. The secondary example is not connected properly so it's broken. Still really good.
– mcv
Nov 8 at 18:51
add a comment |
3 Answers
3
active
oldest
votes
3 Answers
3
active
oldest
votes
active
oldest
votes
active
oldest
votes
up vote
0
down vote
accepted
IFT4S is an array, you can access its objects and their values values by calling:
data.announcements.IFT4S[index].title
with index beeing one of 0-2 here since the array contains 3 objects.
For example:
data.announcements.IFT4S[0].title
This is a very basic concept, check out any javascript guide to learn about arrays.
answered Nov 8 at 16:52
Evoxx
465
add a comment |
up vote
0
down vote
accepted
IFT4S is an array, you can access its objects and their values values by calling:
data.announcements.IFT4S[index].title
with index beeing one of 0-2 here since the array contains 3 objects.
For example:
data.announcements.IFT4S[0].title
This is a very basic concept, check out any javascript guide to learn about arrays.
answered Nov 8 at 16:52
Evoxx
465
add a comment |
up vote
0
down vote
accepted
up vote
0
down vote
accepted
IFT4S is an array, you can access its objects and their values values by calling:
data.announcements.IFT4S[index].title
with index beeing one of 0-2 here since the array contains 3 objects.
For example:
data.announcements.IFT4S[0].title
This is a very basic concept, check out any javascript guide to learn about arrays.
answered Nov 8 at 16:52
Evoxx
465
IFT4S is an array, you can access its objects and their values values by calling:
data.announcements.IFT4S[index].title
with index beeing one of 0-2 here since the array contains 3 objects.
For example:
data.announcements.IFT4S[0].title
This is a very basic concept, check out any javascript guide to learn about arrays.
answered Nov 8 at 16:52
Evoxx
465
answered Nov 8 at 16:52
Evoxx
465
answered Nov 8 at 16:52
Evoxx
465
answered Nov 8 at 16:52
Evoxx
465
465
add a comment |
add a comment |
up vote
1
down vote
when I try data.announcements.IFT4S["title"] or any other key instead
of "title" I get the undefined in the console. What am I doing wrong?
What you are doing here is trying to access the title key of the IFT4S array.
The issue is that IFT4S doesn't have a title key. Instead, like an array object, it has indexes as keys.
IFT4S = [ {...}, {...}, {...} ]
To access the first element of the IFT4S array you would do it like this
IFT4S[0]
In your case that would return the object at the first position of IFT4S array (index 0)
{
id: "D7214",
read_state: "unread",
posted_at: "2018-10-25T14:35:54Z",
title: "Reminder! Systems disruption: 27-28 Oct",
message: "All University online systems will be unavailable."
}
If you want to get all the titles from all the elements inside IFT4S array you could do this
IFT4S.map(element => element.title)
Array.prototype.map returns a new array where each element is the result of applying the function specified inside map to each element of the original array.
In this case, it would return
[
"Reminder! Systems disruption: 27-28 Oct",
"Stem Fair",
"Smile more, worry less with our FREE course"
]
answered Nov 8 at 17:15
Joaquin Timerman
1245
add a comment |
up vote
1
down vote
when I try data.announcements.IFT4S["title"] or any other key instead
of "title" I get the undefined in the console. What am I doing wrong?
What you are doing here is trying to access the title key of the IFT4S array.
The issue is that IFT4S doesn't have a title key. Instead, like an array object, it has indexes as keys.
IFT4S = [ {...}, {...}, {...} ]
To access the first element of the IFT4S array you would do it like this
IFT4S[0]
In your case that would return the object at the first position of IFT4S array (index 0)
{
id: "D7214",
read_state: "unread",
posted_at: "2018-10-25T14:35:54Z",
title: "Reminder! Systems disruption: 27-28 Oct",
message: "All University online systems will be unavailable."
}
If you want to get all the titles from all the elements inside IFT4S array you could do this
IFT4S.map(element => element.title)
Array.prototype.map returns a new array where each element is the result of applying the function specified inside map to each element of the original array.
In this case, it would return
[
"Reminder! Systems disruption: 27-28 Oct",
"Stem Fair",
"Smile more, worry less with our FREE course"
]
answered Nov 8 at 17:15
Joaquin Timerman
1245
add a comment |
up vote
1
down vote
up vote
1
down vote
when I try data.announcements.IFT4S["title"] or any other key instead
of "title" I get the undefined in the console. What am I doing wrong?
What you are doing here is trying to access the title key of the IFT4S array.
The issue is that IFT4S doesn't have a title key. Instead, like an array object, it has indexes as keys.
IFT4S = [ {...}, {...}, {...} ]
To access the first element of the IFT4S array you would do it like this
IFT4S[0]
In your case that would return the object at the first position of IFT4S array (index 0)
{
id: "D7214",
read_state: "unread",
posted_at: "2018-10-25T14:35:54Z",
title: "Reminder! Systems disruption: 27-28 Oct",
message: "All University online systems will be unavailable."
}
If you want to get all the titles from all the elements inside IFT4S array you could do this
IFT4S.map(element => element.title)
Array.prototype.map returns a new array where each element is the result of applying the function specified inside map to each element of the original array.
In this case, it would return
[
"Reminder! Systems disruption: 27-28 Oct",
"Stem Fair",
"Smile more, worry less with our FREE course"
]
answered Nov 8 at 17:15
Joaquin Timerman
1245
when I try data.announcements.IFT4S["title"] or any other key instead
of "title" I get the undefined in the console. What am I doing wrong?
What you are doing here is trying to access the title key of the IFT4S array.
The issue is that IFT4S doesn't have a title key. Instead, like an array object, it has indexes as keys.
IFT4S = [ {...}, {...}, {...} ]
To access the first element of the IFT4S array you would do it like this
IFT4S[0]
In your case that would return the object at the first position of IFT4S array (index 0)
{
id: "D7214",
read_state: "unread",
posted_at: "2018-10-25T14:35:54Z",
title: "Reminder! Systems disruption: 27-28 Oct",
message: "All University online systems will be unavailable."
}
If you want to get all the titles from all the elements inside IFT4S array you could do this
IFT4S.map(element => element.title)
Array.prototype.map returns a new array where each element is the result of applying the function specified inside map to each element of the original array.
In this case, it would return
[
"Reminder! Systems disruption: 27-28 Oct",
"Stem Fair",
"Smile more, worry less with our FREE course"
]
answered Nov 8 at 17:15
Joaquin Timerman
1245
answered Nov 8 at 17:15
Joaquin Timerman
1245
answered Nov 8 at 17:15
Joaquin Timerman
1245
answered Nov 8 at 17:15
Joaquin Timerman
1245
1245
add a comment |
add a comment |
up vote
1
down vote
You have to itrate over the array to get value from an array of object
var data = {
"announcements": {
"IFT4S": [
{
"id": "D7214",
"read_state": "unread",
"posted_at": "2018-10-25T14:35:54Z",
"title": "Reminder! Systems disruption: 27-28 Oct",
"message": "All University online systems will be unavailable."
},
{
"id": "B399C",
"read_state": "read",
"posted_at": "2018-10-22T09:04:48Z",
"title": "Stem Fair",
"message": "The STEM Careers Fair is taking place on 31 October 2018"
},
{
"id": "6F5EE",
"read_state": "unread",
"posted_at": "2018-10-22T09:04:48Z",
"title": "Smile more, worry less with our FREE course",
"message": "Take part in our Online Mindfulness Programme."
},
]
}
}
data.announcements.IFT4S.forEach(item => {
console.log(item.title)
})or you can do like this,
0 is the index
console.log(data.announcements.IFT4S[0].read_state)
console.log(data.announcements.IFT4S[0].title)answered Nov 8 at 16:53
Hafeez Hamza
307110
Nice. Might I suggest using item.title in your working example. The secondary example is not connected properly so it's broken. Still really good.
– mcv
Nov 8 at 18:51
add a comment |
up vote
1
down vote
You have to itrate over the array to get value from an array of object
var data = {
"announcements": {
"IFT4S": [
{
"id": "D7214",
"read_state": "unread",
"posted_at": "2018-10-25T14:35:54Z",
"title": "Reminder! Systems disruption: 27-28 Oct",
"message": "All University online systems will be unavailable."
},
{
"id": "B399C",
"read_state": "read",
"posted_at": "2018-10-22T09:04:48Z",
"title": "Stem Fair",
"message": "The STEM Careers Fair is taking place on 31 October 2018"
},
{
"id": "6F5EE",
"read_state": "unread",
"posted_at": "2018-10-22T09:04:48Z",
"title": "Smile more, worry less with our FREE course",
"message": "Take part in our Online Mindfulness Programme."
},
]
}
}
data.announcements.IFT4S.forEach(item => {
console.log(item.title)
})or you can do like this,
0 is the index
console.log(data.announcements.IFT4S[0].read_state)
console.log(data.announcements.IFT4S[0].title)answered Nov 8 at 16:53
Hafeez Hamza
307110
Nice. Might I suggest using item.title in your working example. The secondary example is not connected properly so it's broken. Still really good.
– mcv
Nov 8 at 18:51
add a comment |
up vote
1
down vote
up vote
1
down vote
You have to itrate over the array to get value from an array of object
var data = {
"announcements": {
"IFT4S": [
{
"id": "D7214",
"read_state": "unread",
"posted_at": "2018-10-25T14:35:54Z",
"title": "Reminder! Systems disruption: 27-28 Oct",
"message": "All University online systems will be unavailable."
},
{
"id": "B399C",
"read_state": "read",
"posted_at": "2018-10-22T09:04:48Z",
"title": "Stem Fair",
"message": "The STEM Careers Fair is taking place on 31 October 2018"
},
{
"id": "6F5EE",
"read_state": "unread",
"posted_at": "2018-10-22T09:04:48Z",
"title": "Smile more, worry less with our FREE course",
"message": "Take part in our Online Mindfulness Programme."
},
]
}
}
data.announcements.IFT4S.forEach(item => {
console.log(item.title)
})or you can do like this,
0 is the index
console.log(data.announcements.IFT4S[0].read_state)
console.log(data.announcements.IFT4S[0].title)answered Nov 8 at 16:53
Hafeez Hamza
307110
You have to itrate over the array to get value from an array of object
var data = {
"announcements": {
"IFT4S": [
{
"id": "D7214",
"read_state": "unread",
"posted_at": "2018-10-25T14:35:54Z",
"title": "Reminder! Systems disruption: 27-28 Oct",
"message": "All University online systems will be unavailable."
},
{
"id": "B399C",
"read_state": "read",
"posted_at": "2018-10-22T09:04:48Z",
"title": "Stem Fair",
"message": "The STEM Careers Fair is taking place on 31 October 2018"
},
{
"id": "6F5EE",
"read_state": "unread",
"posted_at": "2018-10-22T09:04:48Z",
"title": "Smile more, worry less with our FREE course",
"message": "Take part in our Online Mindfulness Programme."
},
]
}
}
data.announcements.IFT4S.forEach(item => {
console.log(item.title)
})or you can do like this,
0 is the index
console.log(data.announcements.IFT4S[0].read_state)
console.log(data.announcements.IFT4S[0].title)var data = {
"announcements": {
"IFT4S": [
{
"id": "D7214",
"read_state": "unread",
"posted_at": "2018-10-25T14:35:54Z",
"title": "Reminder! Systems disruption: 27-28 Oct",
"message": "All University online systems will be unavailable."
},
{
"id": "B399C",
"read_state": "read",
"posted_at": "2018-10-22T09:04:48Z",
"title": "Stem Fair",
"message": "The STEM Careers Fair is taking place on 31 October 2018"
},
{
"id": "6F5EE",
"read_state": "unread",
"posted_at": "2018-10-22T09:04:48Z",
"title": "Smile more, worry less with our FREE course",
"message": "Take part in our Online Mindfulness Programme."
},
]
}
}
data.announcements.IFT4S.forEach(item => {
console.log(item.title)
})var data = {
"announcements": {
"IFT4S": [
{
"id": "D7214",
"read_state": "unread",
"posted_at": "2018-10-25T14:35:54Z",
"title": "Reminder! Systems disruption: 27-28 Oct",
"message": "All University online systems will be unavailable."
},
{
"id": "B399C",
"read_state": "read",
"posted_at": "2018-10-22T09:04:48Z",
"title": "Stem Fair",
"message": "The STEM Careers Fair is taking place on 31 October 2018"
},
{
"id": "6F5EE",
"read_state": "unread",
"posted_at": "2018-10-22T09:04:48Z",
"title": "Smile more, worry less with our FREE course",
"message": "Take part in our Online Mindfulness Programme."
},
]
}
}
data.announcements.IFT4S.forEach(item => {
console.log(item.title)
}) console.log(data.announcements.IFT4S[0].read_state)
console.log(data.announcements.IFT4S[0].title) console.log(data.announcements.IFT4S[0].read_state)
console.log(data.announcements.IFT4S[0].title)answered Nov 8 at 16:53
Hafeez Hamza
307110
edited Nov 9 at 0:32
answered Nov 8 at 16:53
Hafeez Hamza
307110
answered Nov 8 at 16:53
Hafeez Hamza
307110
answered Nov 8 at 16:53
Hafeez Hamza
307110
307110
Nice. Might I suggest using item.title in your working example. The secondary example is not connected properly so it's broken. Still really good.
– mcv
Nov 8 at 18:51
add a comment |
Nice. Might I suggest using item.title in your working example. The secondary example is not connected properly so it's broken. Still really good.
– mcv
Nov 8 at 18:51
Nice. Might I suggest using item.title in your working example. The secondary example is not connected properly so it's broken. Still really good.
– mcv
Nov 8 at 18:51
Nice. Might I suggest using item.title in your working example. The secondary example is not connected properly so it's broken. Still really good.
– mcv
Nov 8 at 18:51
add a comment |
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4
IFT4Sis an array. You will need to iterate over it to access objects. e.g.data.announcements.IFT4S[0]["title"]– Nikhil Aggarwal
Nov 8 at 16:47