How to store a variable in angular which is being subscribed via post as json?

Question

I have a json as like this.

[{"id":"1","date":"2020-02-21","status":"present","studentid":"1"},{"id":"2","date":"2020-02-24","status":"present","studentid":"1"}]

How to store date in a variable using angular which is being subscribe d as http request.I am not able to store .This is what i tried.

 date:string=[];
 sendPostRequest()  {

  var options = { headers: new HttpHeaders({ 'Content-Type': 'text/plain' }) };
   var count=0;
  this.http.post("http://localhost/android/Api.php?apicall=getattendance", this.postData,options).
  pipe(map(res =>  res.results || []))

  .subscribe(data => {
   this.date=data['date'];


  });

please help me.I am new to angular.

what do you mean by global variable? across the application? — Sajeetharan, Feb 24 '20 at 05:06
sorry i mean store it in a variable which is outside subscribe method .here store it in date. — midhunsivarajan, Feb 24 '20 at 05:07
@Kaustubh Khare .This json value keeps on changing by having more number of data.So how can i make it dynamic — midhunsivarajan, Feb 24 '20 at 05:18
just loop through the data that you are receiving inside subscribe function. It will be dynamic — Apurva Pathak, Feb 24 '20 at 05:26
@KaustubhKhare can you please help me by telling the code how to store data in a variable which is being subscribed via http — midhunsivarajan, Feb 24 '20 at 05:29
@midhunsivarajan I have updated my answer. Please try that and let me know if you get any issue. — Kaustubh Khare, Feb 24 '20 at 05:32

score 2 · Answer 1 · answered Feb 24 '20 at 05:14

2

Loop through this json and put it into a new array.

const json = [{ "id": "1", "date": "2020-02-21", "status": "present", "studentid": "1" }, { "id": "2", "date": "2020-02-24", "status": "present", "studentid": "1" }];
const date = [];
json.forEach((item) => {
    date.push({
        date: item.date
    })
})
console.log(date);

answered Feb 24 '20 at 05:14

wsc

916
7
10

this json i am getting while subscribing.Can you please help me by telling how to store the data which is being accepted by subscription – midhunsivarajan Feb 24 '20 at 05:20
This problem is related to the deep and shallow copy of the object. You can learn about this information – wsc Feb 24 '20 at 05:26

Kaustubh Khare · Accepted Answer · 2020-02-24T05:30:45.350

You are getting response as an array. Convert your response to date. Please refer below code where you will get the date from your response.

date:string=[];
 sendPostRequest()  {

  var options = { headers: new HttpHeaders({ 'Content-Type': 'text/plain' }) };
   var count=0;
  this.http.post("http://localhost/android/Api.php?apicall=getattendance", this.postData,options).
  pipe(map(res =>  res.results || []))

  .subscribe(data => {
   this.date=data.map(ele => ele.date);


  });

Example,

const data = [{"id":"1","date":"2020-02-21","status":"present","studentid":"1"},{"id":"2","date":"2020-02-24","status":"present","studentid":"1"}];

const date = data.map(ele => ele.date);

console.log(date);

score 0 · Answer 3 · answered Feb 24 '20 at 05:12

0

your date in string format and it's a single value and declare your date variable as Array [] you just need to declare your date as string variable

date : string =''; or date = '';

answered Feb 24 '20 at 05:12

Irfan Maniyar

1
3

Maaz Ahmed · Answer 4 · 2020-02-25T06:40:35.263

0

I think your question is similar to these already asked questions. If you want to store it in a variable you can look at this one: Store data from API in variable [Angular]

If you want to convert it in date format have a look at it: how to convert current date to YYYY-MM-DD format with angular 2

UPDATE

I think the only problem is not iterating properly. Something like this would be okay.

Iterate over your response and push the element to your list

.subscribe(data => {
  data.forEach((item) => {
      date.push({
          date: item.date
      })
  })
})

edited Feb 25 '20 at 06:40

answered Feb 24 '20 at 05:21

Maaz Ahmed

53
1
6

Thanks for trying to help me.but i want only date.not the entire json.can you please help me by telling how to do that – midhunsivarajan Feb 24 '20 at 05:31

score 0 · Answer 5 · answered Feb 24 '20 at 05:22

Understand the structure of your JSON well at first. For that you can use online JSON parser available for free:

https://codebeautify.org/jsonviewer

https://jsonformatter.org/

http://json.parser.online.fr/

If you see you data after structure it is;

[
  {
    "id": "1",
    "date": "2020-02-21",
    "status": "present",
    "studentid": "1"
  },
  {
    "id": "2",
    "date": "2020-02-24",
    "status": "present",
    "studentid": "1"
  }

]

There is an array of object. So basically, you have too loop through the array visit every index of array and then pick the key-value pair that you want.

@wsc answer pointed the code well.

score 0 · Answer 6 · answered Feb 24 '20 at 05:26

0

Your response is an array of objects. Define your date variable as data:string='';

and try this.date=data[0].date

if you get any error please update.

answered Feb 24 '20 at 05:26

Neeraj Kumar Prajapati

3
1

score 0 · Answer 7 · answered Feb 24 '20 at 08:52

    date:string=[];
 sendPostRequest()  {

  var options = { headers: new HttpHeaders({ 'Content-Type': 'text/plain' }) };
   var count=0;
  this.http.post("http://localhost/android/Api.php?apicall=getattendance", this.postData,options).
  pipe(map(res =>  res.results || []))

  .subscribe(data => {
  data.forEach(element=>{
this.date.push(element.date);
})

});

How to store a variable in angular which is being subscribed via post as json?

7 Answers7