Keydown Event not working properly

Methoun Ahmed

Here is my code.

private void Total_Amount_KeyDown(object sender, KeyEventArgs e)
{
try
{
double a = Convert.ToDouble(txtOldAmt.Text);
double b = Convert.ToDouble(txtDeposit_Amt.Text);
txtTotal.Text = (a + b).ToString();
}
catch (Exception)
{
MessageBox.Show("Invalid input");
}
}

10 Replies

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Tapan Patel9y ago
Accepted answer
correct event would be KeyUp - when the key is released.

try this. Also, try adding some null/empty string checks around to avoid error.
private void textBox3_KeyUp(object sender, KeyEventArgs e)
        {
            var x = Convert.ToDouble(textBox2.Text) + Convert.ToDouble(textBox3.Text);
            textBox4.Text = x.ToString();
        }
0
Ramesh Palanivel9y ago
Hi Methoun,Just copy your code and paste it in deposit textbox key down event.. Surely it will work
-1
Methoun Ahmed9y ago
txtOld.txt get value from database when I entered txtDeposit.txt value automatic show sum value in txtTotal.txt text field.That's it
0
Ramesh Palanivel9y ago
Hi Methoun, When the calculation want to perform? While entering txtold_amt value or?
0
Methoun Ahmed9y ago
Does't work
0
Ramesh Palanivel9y ago
Hi Methoun,

First remove the code from txtTotal_amt_keypress event.

Write the same code in txtOld_amt_keypress event,

You can achieve this calculation in two ways, after entering old amount and clicking the enter button, find the sample code,
private void txtOldAmount_KeyDown(object sender, KeyEventArgs e)
{
    if (e.KeyCode == Keys.Enter)
{
txtTotalAmount.Text = Convert.ToString(Convert.ToInt32(txtOldAmount.Text) + Convert.ToInt32(txtDepositAmount.Text));
}
}
Or after leaving the textbox we can perform the same calculation,
private void txtOldAmount_Leave(object sender, EventArgs e)
{
txtTotalAmount.Text = Convert.ToString(Convert.ToInt32(txtOldAmount.Text) + Convert.ToInt32(txtDepositAmount.Text));
}
0
Methoun Ahmed9y ago
I want to txtOldAmt.Text and txtDeposit_Amt.Text Sum value show in txtTotal.Text automatic
0
Ramesh Palanivel9y ago
Hi Methoun,

What is your exact requirement? Do want to perform this calculation depends on any particular key press ex : enter key event or someother key..

Or if you want to perform this calculation while leaving from this textbox?

Pls mention it...
0
Methoun Ahmed9y ago
Yes,If press any key than show result.Other wise result not show my text box
0
Ramesh Palanivel9y ago
Hi Methoun,

Have you faced any errors or no calculation happed?
0