Question

I have been saving into the ComboBox a value out of the selected column in datagridview with below code.
My question is:How can I prevent duplicate records when I save the values into the ComboBox? How can I do that?

Code:

int ColumnIndex = dgUretimListesi.CurrentCell.ColumnIndex;          
CmbAra.Text = "";

for (int i = 0; i < dgUretimListesi.Rows.Count; i++)
{
    CmbAra.Items.Add(dgUretimListesi.Rows.Cells[ColumnIndex].Value.ToString());
}

Answer 1

you could first transfer your datagridview items to a dictionary (which guarantees uniqueness) and then transfer that dictionary content to the combobox. or you could check for uniqueness yourself using a ‘Contains’ method on the combobox. you could even tie the dictionary to the combobox as a source for the combobox items.

Dictionary<string,bool> d = new Dictionary<string,bool>();
int ColumnIndex = dgUretimListesi.CurrentCell.ColumnIndex;
CmbAra.Text = "";
for (int i = 0; i < dgUretimListesi.Rows.Count; i++)
{
   d[dgUretimListesi.Rows.Cells[ColumnIndex].Value.ToString()] = true;
}
CmbAra.Items.AddRange(d.Keys);