Tips for saving a variable in Angular that is being received through a subscription as JSON:

Question

Tips for saving a variable in Angular that is being received through a subscription as JSON:

Below is an example of the json I have:

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

I am struggling to store the date in a variable using Angular when it is being subscribed as an http request. Here is what I have attempted so far:

 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'];


  });

I would greatly appreciate any assistance as I am new to Angular.

angular typescript ionic4

Answer 1

Answer №1

If you are receiving a response in the form of an array, you can convert that response to a date format. Below is a sample code snippet demonstrating how you can extract 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);


  });

Here is an 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);

Answer 2

If you are receiving a response in the form of an array, you can convert that response to a date format. Below is a sample code snippet demonstrating how you can extract 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);


  });

Here is an 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);

Answer 3

Answer №2

Iterate over the JSON data and store it in 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 datesArray = [];
json.forEach((item) => {
    datesArray.push({
        date: item.date
    })
})
console.log(datesArray);

Answer 4

Iterate over the JSON data and store it in 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 datesArray = [];
json.forEach((item) => {
    datesArray.push({
        date: item.date
    })
})
console.log(datesArray);

Answer 5

Answer №3

To represent your date in string format as a single value, you can declare your date variable as an Array []. Simply define your date as a string variable like so:

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

Answer 6

To represent your date in string format as a single value, you can declare your date variable as an Array []. Simply define your date as a string variable like so:

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

Answer 7

Answer №4

It is crucial to have a good understanding of the structure of your JSON data right from the start. You can make use of various online JSON parsers which are readily available for free:

If you analyze your data after organizing its structure, it will look like this:

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

]

The data consists of an array of objects. Therefore, it is essential to loop through each index of the array and extract the required key-value pairs.

The code provided by @wsc offers valuable insights into handling this task effectively.

Answer 8

It is crucial to have a good understanding of the structure of your JSON data right from the start. You can make use of various online JSON parsers which are readily available for free:

If you analyze your data after organizing its structure, it will look like this:

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

]

The data consists of an array of objects. Therefore, it is essential to loop through each index of the array and extract the required key-value pairs.

The code provided by @wsc offers valuable insights into handling this task effectively.

Answer 9

Answer №5

The result you receive consists of a series of objects. Assign an empty string to the variable 'date' by typing data:string='';

Then, attempt this: this.date=data[0].date

In case of any errors, make sure to revise accordingly.

Answer 10

The result you receive consists of a series of objects. Assign an empty string to the variable 'date' by typing data:string='';

Then, attempt this: this.date=data[0].date

In case of any errors, make sure to revise accordingly.

Answer 11

Answer №6


    let datesArray: 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 => {
                    datesArray.push(element.date);
                })
            });

});

Answer 12


    let datesArray: 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 => {
                    datesArray.push(element.date);
                })
            });

});

Answer 13

Answer №7

It seems like your query is closely related to some existing questions that have been asked before. If you're looking to save it as a variable, you might find this helpful: Storing API Data in a Variable [Angular]

For converting it into a date format, you can refer to this post: How to Convert Current Date to YYYY-MM-DD Format using Angular 2

UPDATE

This issue may arise from a problem with iteration. An approach like the following should work fine.

Simply loop through your response and add each element to your list:

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

Answer 14

It seems like your query is closely related to some existing questions that have been asked before. If you're looking to save it as a variable, you might find this helpful: Storing API Data in a Variable [Angular]

For converting it into a date format, you can refer to this post: How to Convert Current Date to YYYY-MM-DD Format using Angular 2

UPDATE

This issue may arise from a problem with iteration. An approach like the following should work fine.

Simply loop through your response and add each element to your list:

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

Tips for saving a variable in Angular that is being received through a subscription as JSON:

Answer №1

Answer №2

Answer №3

Answer №4

Answer №5

Answer №6

Answer №7

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