//to check if some information user put is empty or invalid.
bool IsItemDataValid()
{
//Check if an user input empty information
if (ItemNameTxtbox.Text == "" || ItemPriceTxtbox.Text == "" || ItemQuantTxtbox.Text == "")
{
//Place the focus on the first invalid textbox
if (ItemNameTxtbox.Text == "")
{
ItemNameTxtbox.Focus();
}
if (ItemPriceTxtbox.Text == "")
{
ItemPriceTxtbox.Focus();
}
if (ItemQuantTxtbox.Text == "")
{
ItemQuantTxtbox.Focus();
}
return(false);
}
//Check if the number an user input is negative
else if (Convert.ToDecimal(ItemPriceTxtbox.Text) <= 0 || (Convert.ToInt32(ItemQuantTxtbox.Text) <= 0))
{
//Place the focus on the first invalid textbox
if (ItemPriceTxtbox.Text == "")
{
ItemPriceTxtbox.Focus();
}
if (ItemQuantTxtbox.Text == "")
{
ItemQuantTxtbox.Focus();
}
return(false);
}
else
{
return(true);
}
}
