如何从Angular中的另一个函数调用一个函数？

Question

onFileSelected(event) is called when file is selected from input type (from Home.html ), everything works fine except when I try to call this.callproducts(data,0,c_altcode) .

Below is my home.ts code, where am I going wrong?

 onFileSelected(event)
  {
    var file = event.target.files[0];
        ...// some code here
    oReq.onload = function(e) {
        ...// some code here

if(oReq.status === 200)
          { 
            if(final_arr[0].hasOwnProperty("Altcode"))
            {
              var c_altcode =final_arr[0].hasOwnProperty("Altcode");

         // error coming in below line when i am trying to call this function which is outside `onFileSelected` function. 
          this.callproducts(data,0,c_altcode);           
                }

          }
        }

        oReq.send(null);
  }


callproducts(a,b,c,d){
...//some code here
}

Error coming when I am trying to call this function which is outside of onFileSelected function. The error is:

[ts] Property 'callproducts' does not exist on type 'XMLHttpRequest'

Answer 1

"this" is equal to "oReq" if I am correct. I don't believe that "this." Is right. Try just callProducts without this.

Answer 2

You cannot call this.callproducts(data,0,c_altcode) inside another function because it is not in your component's scope.

But you can try below.

export class HomePage {

  constructor() {}

 onFileSelected(event) {

    let file = event.target.files[0];

    oReq.onload = function(e) {

        if(oReq.status === 200) { 

            if(final_arr[0].hasOwnProperty("Altcode")) {

              let c_altcode =final_arr[0].hasOwnProperty("Altcode");
              HomePage.callproducts(data,0,c_altcode);           
            }
          }
        }
        oReq.send(null);
  }

static callproducts(a,b,c,d){

  }
}