How do I get my object to stick and not keep resetting to null.

[Nathan Milota]

The item object keeps going to null and I cannot use it in a loop or where I need to.  

  checkIfItemExists(){      console.log(this.item);      this.itemService.getItemsByCompanyNum(LoginComponent.companyNum).      subscribe(        response=>{        this.items=response;              for(let i=0; i<this.items.length; i++){          console.log(this.item);          if(this.item.name.toUpperCase()== this.items[i].name.toUpperCase()){            alert("You already have an item named "+this.item.name+".")            this.itemChecked=true;         }           this.onSubmit();         }        }      )         }

When I log the item to the console the second time, it goes to null.   How do I stop that from happening?

[Les Morgan]

Nathan,
I do not see anywhere relevant to where you initialize response.  you that a setter for response that relies on response already being set, so this code, imo, is not the problem.
Les

[Nathan Milota]

Why does it go to null then?

[Paul Clapham]

I don't think anything "goes to null". What I think is that "this" refers to different things at different places in that code, and you're assuming that it's always the same.

[Nathan Milota]

How do I keep it the same?

[Nathan Milota]

I've tried this several different ways.   I even put an input as a typescript variable and pass it in the loop, but it always becomes null when I try to use it.  It doesn't do this in Java.  There is something wrong with the way this language works I think.

[Ron McLeod]

this => blog post may help.

[Nathan Milota]

It took me awhile, but this finally fixed it.  


onSubmit(){  var itemStringReceived= localStorage.getItem('itemStringKey');  var itemDescriptionStringReceived= localStorage.getItem('itemDescriptionKey');  this.item.name= itemStringReceived;  this.item.description= itemDescriptionStringReceived;      if(this.id===undefined){        console.log(this.itemChecked);        if(this.itemChecked===true){          return;        }                      this.item.companyNum= LoginComponent.companyNum;        this.itemService.createItem(this.item).subscribe(           data=> (console.log(data)            )         );        alert("Item created");        this.router.navigateByUrl('/new-item');      }      else{        if(this.itemChecked===true){          return;        }        this.itemService.updateItem(this.id, this.item).subscribe(          data=>{            console.log(data)            this.router.navigate(['edit-delete-item']);          }        )      }  }  checkIfItemExists(){      var itemString= this.itemName.toString();      localStorage.setItem('itemStringKey', itemString);      var itemDescriptionString= this.itemDescription.toString();      localStorage.setItem('itemDescriptionKey', itemDescriptionString);    this.itemService.getItemsByCompanyNum(LoginComponent.companyNum).      subscribe(        response=>{        this.items=response;         var itemStringReceived= localStorage.getItem('itemStringKey');                for(let i=0; i<this.items.length; i++){          console.log(itemStringReceived+" "+ this.items[i].name);                    if(itemStringReceived!.toUpperCase().trim()=== this.items[i].name.toUpperCase().trim()){            alert("You already have an item named "+itemStringReceived+".")            this.itemChecked=true;            return;         }                   }         this.onSubmit();        }      )         }


I had to do an ngModel for the varaibles itemName and itemDescription, put them into local Storage, retrieve them in the onSubmit() method so they wouldn't be null, and now it works.