السلام عليكم تظهر رساله الخطأ Specified cast is not valid في الكود التالي
protected void Button8_Click(object sender, EventArgs e)
{
SqlCommand cmd = new SqlCommand("SELECT cast(salary.home as float)+cast(salary.transfer as float)+cast(salary.mobile as float)+cast(salary.salary as float)-SUM(cast(penalty.discount as float))-SUM (cast(absence.leat as float))*salary.salary/240-COUNT(cast(absence.absence as varchar))* salary.salary/30+SUM (cast(absence.overtime as float))*salary.salary/240 FROM salary INNER JOIN absence ON salary.code = absence.code INNER JOIN penalty ON salary.code = penalty.code where salary.code=@code group by salary.salary,salary.home,salary.transfer,salary.mobile ", con);
string code = "-1";
if (DropDownList1.SelectedItem.Text.ToString() != "")
code = DropDownList1.SelectedItem.Text.ToString();
cmd.Parameters.AddWithValue(
"@code", code);
con.Open()
var rowcount = (int)cmd.ExecuteScalar();
TextBox1.Text = rowcount.ToString();
con.Close();
}