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The updated state in one function is not in sync with the other function, which sends it to the API

When I click on this button:

<Button
  onClick={(e) => {
    addToCard(item);
    handleprisma();
  }}
>
  add to cart
</Button>

This function wants to add the item to my card:

  const addToCard = (item) => {
    const newCard = {
      fff: "1",
      ddd:  "2",
      aa: "3",
      dfdfdf:  "4",
      asdf:  "5",
      teest:  "6",
    
    };
    context.setcount(context.count + 1);
    context.setcard((prev) => [...prev, newCard]);
  };

And this one wants to send it to my database:

  const testtt= context.card;
  async function handleprisma() {
    const res = await axios.post('/api/Me', {
      testtt,
    });
    console.log(res.data);
  }

And by default, the value of the card is [] so I think when I click on the button it does not run the addToCard! But on the second click in the database, I see that the array that should have been created on the first click is there, and when I click again, I see that the array that should have been created on the second click is there.

I solved this problem with this:

  useEffect(() => {
    if (context.card.length !== 0) {
      handleprisma();
    }
   
  }, [addToCard]);


So when I have 1 item in my card and if I refresh the page, 3 or 4 new copies of the same thing will be created in the database, so how can I just stop getting those copies?

I wanted to use useCallback to solve this problem so I converted that useEffect to:

  useCallback(() => {
    if (context.card.length !== 0) {
      handleprisma();
    }
    console.log('sfd');
  }, [addToCard]);

and to:

  useCallback(() => {
    if (context.card.length !== 0) {
      handleprisma();
    }
    console.log('sfd');
  }, [context.card]);

But why is nothing happening when I click on the button?

Via Active questions tagged javascript - Stack Overflow https://ift.tt/74UcPJO

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