Input string was not in a correct format.

Question

Hello Team,

When I Add Item to the list, I want the itme qty, totalprice, total tax,amount received, change, grandtotal and overallgrand total listed in the lables.

public void CalculateTotal()
{
//int i = 0;

decimal Sum = 0;
decimal SubTotal = 0;
decimal tax = 0;
decimal discount = decimal.Parse(txt_Discount.Text);
decimal totalPrice = decimal.Parse(lbl_TotalPrice.Text);
decimal percentageDiscount = decimal.Parse(lbl_Discount.Text);

for (int i = 0; i <dataGridView1.Rows.Count; i++)
{


Sum =Convert.ToDecimal(Sum + dataGridView1.Rows[i].Cells[9].Value.ToString());
tax = Convert.ToDecimal(tax + dataGridView1.Rows[i].Cells[4].Value.ToString())/100 * int.Parse(dataGridView1.Rows[i].Cells[7].ToString()) * Convert.ToDecimal(dataGridView1.Rows[i].Cells[6].ToString());
SubTotal= (Convert.ToDecimal(tax + dataGridView1.Rows[i].Cells[4].Value.ToString()) * int.Parse(dataGridView1.Rows[i].Cells[7].ToString()));

lbl_NoOfItems.Text = (dataGridView1.Rows.Count -1 + 1).ToString();
lbl_SubTotal.Text = SubTotal.ToString("#,##0.00");
lbl_TotalTax.Text = Convert.ToDecimal(tax + SubTotal).ToString("#,##0.00");
lbl_Discount.Text = Convert.ToDecimal(discount * totalPrice / 100).ToString("#,##0.00");
lbl_GrandTotal.Text =Convert.ToDecimal(totalPrice * percentageDiscount).ToString("#,##0.00");

lbl_OverallGrandTotal.Text = Convert.ToDecimal(lbl_GrandTotal.Text).ToString("#,##0.00");
}

}

am also having a feedback from this variable saying that input string not in correct format.

decimal discount = decimal.Parse(txt_Discount.Text);

and in the dataGridView I hide the first column

Sarthak Varshney · Answer

It looks like you're having some issues with calculating totals and handling data from your DataGridView. Let's address both the calculations and the input string format issues. First, the input string format error is likely occurring because the txt_Discount.Text might be empty or contain non-numeric values. You can handle this by using decimal.TryParse instead of decimal.Parse to avoid exceptions. Next, let's ensure that the calculations for the quantities, prices, taxes, discounts, and totals are correct and clear. Here’s a revised version of your CalculateTotal method: public void CalculateTotal() { decimal sum = 0; decimal subTotal = 0; decimal tax = 0; decimal discount = 0; decimal totalPrice = 0; decimal percentageDiscount = 0; // Check if txt_Discount.Text is a valid decimal if (!decimal.TryParse(txt_Discount.Text, out discount)) { discount = 0; // Default discount to 0 if the input is invalid } // Check if lbl_TotalPrice.Text is a valid decimal if (!decimal.TryParse(lbl_TotalPrice.Text, out totalPrice)) { totalPrice = 0; // Default total price to 0 if the input is invalid } // Check if lbl_Discount.Text is a valid decimal if (!decimal.TryParse(lbl_Discount.Text, out percentageDiscount)) { percentageDiscount = 0; // Default percentage discount to 0 if the input is invalid } int itemCount = 0; for (int i = 0; i Key Changes: Input Validation: Using decimal.TryParse to safely parse the input values, avoiding exceptions if the input is not in the correct format. Correct Calculations: Ensure all the calculations for total price, tax, discount, and grand total are accurate. Handling Empty Rows: Adding a check to skip empty rows in the DataGridView. This should resolve the input format error and ensure your calculations are correct. Adjust any column indices or other specific logic as needed based on your actual DataGridView setup.

Sarthak Varshney · Answer

It seems like the calculation for the total tax is still problematic. Let's focus on ensuring that the tax calculation correctly reads from the DataGridView and sums up the values. Below is an adjusted version of your CalculateTotal method that emphasizes the correct calculation of the tax column: public void CalculateTotal() { decimal sum = 0; decimal subTotal = 0; decimal totalTax = 0; decimal discount = 0; decimal totalPrice = 0; decimal percentageDiscount = 0; // Check if txt_Discount.Text is a valid decimal if (!decimal.TryParse(txt_Discount.Text, out discount)) { discount = 0; // Default discount to 0 if the input is invalid } // Check if lbl_TotalPrice.Text is a valid decimal if (!decimal.TryParse(lbl_TotalPrice.Text, out totalPrice)) { totalPrice = 0; // Default total price to 0 if the input is invalid } // Check if lbl_Discount.Text is a valid decimal if (!decimal.TryParse(lbl_Discount.Text, out percentageDiscount)) { percentageDiscount = 0; // Default percentage discount to 0 if the input is invalid } int itemCount = 0; for (int i = 0; i Key Points: Row Validation: Ensure each row is not empty before performing calculations. Tax Calculation: Correctly calculate the tax by taking the tax percentage from the DataGridView and applying it to the row total. Accurate Summation: Sum up the totals correctly for the number of items, subtotal, total tax, discount, and grand total. Make sure the column indices in the code (such as Cells[6] , Cells[4] , and Cells[7] ) correctly correspond to the Price , Tax % , and Quantity columns in your DataGridView. This approach should ensure the tax is calculated correctly and displayed in the label. If there are still issues, please verify the content and format of the data in your DataGridView.

Emmmanuel FIADUFE · Answer

Hello Sartha, I have been able to modify part of the code and is no longer over calculating the overallgrandTotal but the only problem is the total tax is not able to calculate the tax column in the DataGridView into the label

Emmmanuel FIADUFE · Answer

Hello Sarthak Thank you so much, but there is one issue here. the Tax has been added to the subtotal at the stockin page already, there is over calculating of overallgrandTotal, the item quantity, and the price sum up should be equal to subtotal and I want only the tax coulmns calculated in the lable and as you can see in the snip shot and additionally when I enter the discount the value of the overallgrandTotal doesn't change