What is the best way to change an array element into a string in TypeScript?

Within my Angular 2 component, I am utilizing an array named fieldlist which is populated by data retrieved from an http.get request. The array is declared as follows:

fieldlist: string[] = [];

I populate this array by iterating through the JSON response obtained from the http.get request.

this.http.get(getform_endpoint,requestOptions).map((res: 
                Response) => res.json()).subscribe(
                    res => { 

            this.FormData = res.schema;

            res.fields.forEach(element => {
                this.fieldlist.push(element);
            });

});  

In a separate function, I attempt to combine the elements of fieldlist into a single string using the join() method:

create_hidden_qp() {

    let elementsnamevalue = this.fieldlist.join();
    console.log("hello", this.fieldlist.join());

}

However, when I convert the array to a string in this manner, it returns an empty response. On the other hand, when I log the array directly, the elements are displayed correctly:

console.log("hello", this.fieldlist);

The output shows the array contents as expected:

hello[] 0 :"userroleid" 1: "ruletype" 2: "employeeid"

Where could I be going wrong?

A) Incorrect declaration? b) Improper assignment? c) Incorrect access to array elements?

Answer №1

Make sure to invoke the create_hidden_qp function only after your request has completed:

this.http.get(getform_endpoint,requestOptions).map(r => r.json()).subscribe(res => { 
  this.FormData = res.schema;

  res.fields.forEach(element => {
    this.fieldlist.push(element);
  });

  this.create_hidden_qp();
});  

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