I'm searching by the ids in the array. But if the array is empty, I want all the data to come. How can I do it?

selectedUrunGrubus: number[] = [];

urun: Urun[];

getUruns() {

this.generic?.Get_All("Uruns/Generic_Method").pipe(map(hizmets => hizmets.filter(hizmets => (this.selectedUrunGrubus.includes(hizmets.urunGrubuID) && this.selectedUrunGrubus.length>0)))).subscribe({
  next: (data) => { this.urun = data; console.log(this.urun) },
  error: (err) => { console.log(err) },
  complete: () => {
  
  }
});

}

this.urun = [id=1] [id=2] [id=3] [id=4];
if(selectedUrunGrubus == [1,2])
{
this.urun = [id=1] [id=2]
}
if(selectedUrunGrubus == empty)
{
this.urun = [id=1] [id=2] [id=3] [id=4]
}

CodePudding user response：

The reason why your array is empty is because of the this.selectedUrunGrubus.length>0 conditional inside your filter. The length of selectedUrunGrubus starts at 0, so the expression will always be false.

Here's another strategy you can use. Assign the filtered array to a variable, then return a ternary expression for either case.

selectedUrunGrubus: number[] = [];

urun: Urun[];

getUruns() {

this.generic?.Get_All("Uruns/Generic_Method")
  .pipe(
    map(hizmets =>{ 
      const matches = hizmets.filter(hizmet => this.selectedUrunGrubus.includes(hizmet.urunGrubuID));
      return !!matches.length ? matches : hizmets;
    }),
    tap(urun=> this.urun = urun)
  ).subscribe();
}

Note:

• I used double bangs !! to convert the length into a boolean (since 0 is falsy)
• Use tap() to handle side effects like property assignments.
• The rest of your logic inside subscribe() is default behavior, so you can just use a basic subscribe() at the end.