Input string was not in a correct format.

Dawood Abbas

11y403.NET

How to multiply or add two textboxes double typed values?

7 Replies

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Dawood Abbas11y ago
public void ddlPackPriceBind()
{
try
{
//open the db connection if it is closed...
if (connection.State == ConnectionState.Closed)
connection.Open();

string packNameEdit = ddlPackName.SelectedItem.ToString();
command = new SqlCommand();
command.CommandText = "sp_Get_PackPrice";
command.CommandType = CommandType.StoredProcedure;
command.Parameters.Add("@packageName", packNameEdit);
da = new SqlDataAdapter(command);
command.Connection = connection;
ds = new DataSet();
da.Fill(ds);
txtAmntToPay.Text = "";
txtAmntToPay.Text = ds.Tables[0].Rows[0]["PackagePrice"].ToString();

}

protected void ddlPackName_SelectedIndexChanged(object sender, EventArgs e)
{
ddlPackPriceBind();
regCustCalculation();
}
Dawood Abbas11y ago
I written like below code but when i enter value second time in other textboxes assing/subtracting again

public void regCustCalculation()
{

double amountToPay = double.Parse(txtAmntToPay.Text);
double noOfConn = double.Parse(txtNoOfConn.Text);
double chargePerConn = double.Parse(txtChargePerConn.Text);
double installCharge = double.Parse(txtInstallCharge.Text);
double discount = double.Parse(txtDiscount.Text);
double packPrice = double.Parse(txtAmntToPay.Text);

if (ddlPackName.SelectedIndex != 0)
{
txtAmntToPay.Text = "0";

packPrice = amountToPay;
packPrice = amountToPay + (noOfConn * chargePerConn);
packPrice = packPrice + installCharge;
packPrice = packPrice - discount;
txtAmntToPay.Text = packPrice.ToString();

}
if (ddlPackName.SelectedIndex==0)
{
txtAmntToPay.Text = "0";

packPrice = noOfConn * chargePerConn;
packPrice = packPrice + installCharge;
packPrice = packPrice - discount;
txtAmntToPay.Text = packPrice.ToString();
}
}

protected void txtNoOfConn_TextChanged(object sender, EventArgs e)
{
//regCustCalculation();
}

protected void txtChargePerConn_TextChanged(object sender, EventArgs e)
{
regCustCalculation();
}

protected void txtInstallCharge_TextChanged(object sender, EventArgs e)
{
regCustCalculation();
}

protected void txtDiscount_TextChanged(object sender, EventArgs e)
{

regCustCalculation();
}
Dawood Abbas11y ago

Package Name:

ddlPackName

No. of Extra Connection:

txtNoConn

Charges per Connection(If any):

txtChargeConn

Installation Charges:

txtInstlChrge

Discount (if any):

txtDisc

Amount to Pay:

txtAmntToPay

Paying Amount:

txtPayAmnt

Balance:

txtBlnc

How to get final result1 (txtAmntToPay.text)? and final result2 (txtBlnc)

1).if I select 'ddlPackName' then its price display in 'txtAmntToPay.text'
2).if I enter 'txtNoConn' and 'txtChargeConn' then multiple this both and add with 'ddlpackname' then display in 'txtamnttoPay'

if I not select 'ddlpackname' then display multiplied values.
3).like this all textboxes values add with 'txtPayAmnt' and subtract 'txtDisc'
Khargesh Rajput11y ago
double amount = Convert.ToDouble(txtAmount.Text);

use convert in uppercase with c
Jignesh Trivedi11y ago
Hi,
here Textbox1.text and textbox2.text is your textbox value.
also double.tryparse function return 0 if function is fail to convert value to double.
Please refer below link for more information.
https://msdn.microsoft.com/en-us/library/3s27fasw(v=vs.110).aspx
can you please share textbox value?
Dawood Abbas11y ago
there showing underline error on .'Text'
like below
double does not contain a definition for 'Text' and no extension methode 'Text accepting a first argument of type 'double' could be found (are you missing a using directive or and assemble reference?)

I tried alredy and also like below

double amount =convert.ToDouble(txtamount.Text);

here also showing same above error message.
Jignesh Trivedi11y ago
Hi,
Textbox always contains string value so you have to cast this value to double.

try this....
double number;
double number1;
Double.TryParse(Textbox1.Text, out number);
Double.TryParse(Textbox2.Text, out number1);
double sum = number+number1;
hope this will help you.