dtpFromDate & dtpTodate are DateTimepickers and a TextBox txtNoofDays

private void dtpFromDate_ValueChanged(object sender, eventArgs e)
{
double value=Convert.ToDouble(txtNoOfdays.Text);
dtpToDate.Value=dtpFromDate.Value.AddDays(value);
}

Here I got the error at--> //double value ----
Input string was not in correct format

How to resolve It.

you get that error if text box is empty, if you want to add nothing if textbox is empty then try

double value = 0;

double.TryParse(txtNoOfdays.Text, out value); // trying to parse if not possible value will remain 0

dtpToDate.Value = dtpFromDate.Value.AddDays(value);

---

Arjun Paudel

you get that error if text box is empty, if you want to add nothing if textbox is empty then try

double value = 0;

double.TryParse(txtNoOfdays.Text, out value); // trying to parse if not possible value will remain 0

dtpToDate.Value = dtpFromDate.Value.AddDays(value);

---

Arjun Paudel