'System.DateTime'不包含'Value'的定义，也没有接受第一个参数'Value'扩展方法

Question

当我尝试调试时，它给出了两个错误：

错误1'System.DateTime'不包含"值"的定义 并且没有扩展方法"值"接受类型的第一个参数 可以找到'System.DateTime'（您是Missi enter code here ng a 使用指令或组件 参考？）c： users home documents Visual Studio 2012 projects windowsformsapplication1 windowsformsapplication1 form1.cs 28 44 windowsformsapplication1

错误2'System.DateTime'不包含"值"的定义 并且没有扩展方法"值"接受类型的第一个参数 可以找到" system.dateTime"（您是否缺少使用指令或 汇编引用？）c： users home documents Visual Studio 2012 projects windowsformsapplication1 windowsformsapplication1 form1.cs 29 40 WindowsFormsApplication1

static string connection = @"Data Source=AmayaSQLEXPRESS;Initial Catalog=myDB;Integrated Security=True";
    SqlConnection con = new SqlConnection(connection);
    double driverCharge;
    private void btnCalculate_Click(object sender, EventArgs e)
    {
        DateTime startDate = dtp_rentedDate.Value;
        DateTime endDate = dtp_returnedDate.Value;
        int startKm = int.Parse(txtstart_Km.Text);
        int endKm = int.Parse(txtend_Km.Text);
        string Veh_ID = cmb_VID.SelectedValue.ToString();
        double basicCharge = 0.0;

namespace WindowsFormsApplication1

{ 公共部分班级表格3：表格 { 公共形式3（） { InitializeComponent（）; fillcombobox（）; }

    static string connection = @"Data Source=DESKTOP-RFLE48TSQLEXPRESS;Initial Catalog=Ayubo_Drive;Integrated Security=True";
    SqlConnection con = new SqlConnection(connection);
    double driverCharge;
    private void btnCalculate_Click(object sender, EventArgs e)
    {
        DateTime startDate = startDate.Value;
        DateTime endDate = endDate.Value;
        int startKm = int.Parse(txtstart_Km.Text);
        int endKm = int.Parse(txtend_Km.Text);
        string Veh_ID = comboBox1.SelectedValue.ToString();
        double basicCharge = 0.0;

        if (rbRent.Checked)
        {
            basicCharge = rentcalculation(Veh_ID, startDate, endDate, false);
        }
        else if (rbRentW_driver.Checked)
        {
            basicCharge = rentcalculation(Veh_ID, startDate, endDate, true);
        }

        txt_basic.Text = String.Format("{0:.00}", basicCharge);
    }
    private void FillComboBox()
    {
        SqlDataAdapter da = new SqlDataAdapter("Select V_ID from Vehicle_Type", con);
        DataTable dt = new DataTable();
        da.Fill(dt);
        comboBox1.DataSource = dt;
        comboBox1.DisplayMember = "V_ID";
        comboBox1.ValueMember = "V_ID";
    }

    public double rentcalculation(string Veh_ID, DateTime startDate, DateTime endDate, bool withDriver)
    {
        double rent = 0.0;
        try
        {
            SqlCommand cmd = new SqlCommand("SELECT * FROM Vehicle_Type  WHERE V_ID=@001", con);
            cmd.Parameters.AddWithValue("@001", Veh_ID);
            con.Open();
            SqlDataReader r = cmd.ExecuteReader();
            if (r.Read())
            {
                double daycharge = double.Parse(r["V_dayRent"].ToString());
                double weekcharge = double.Parse(r["v_weekRent"].ToString());
                double monthlycharge = double.Parse(r["v_monthlyRent"].ToString());
                driverCharge = double.Parse(r["v_driverCharge"].ToString());
                TimeSpan ts = endDate.Date - startDate.Date;
                int total_Days = ts.Days + 1;
                int Days = total_Days;
                int month = (int)Days / 30;
                Days = Days % 30;
                int weekCount = (int)Days / 7;
                Days = Days % 7;
                rent = month * monthlycharge + weekCount * weekcharge + Days * daycharge;
                if (withDriver)
                {
                    driverCharge = total_Days * driverCharge;
                    txt_driver.Text = driverCharge.ToString();
                    double totCharge = rent + driverCharge;
                    txt_total.Text = totCharge.ToString();
                }
                else
                {
                    txt_driver.Text = "0.0";
                    txt_total.Text = rent.ToString();  
                }

            }
        }
        catch (SqlException e)
        {
            e.ToString();
        }
        finally
        {
                con.Close();
        }
        return rent;
    }
}

}

Answer 1

dtp_renteddate对象的数据类型是什么？看来是系统的。在这里您可以看到的，它确实不包含"价值"属性。我认为您想使用其他一些变量，该变量是可用于在GUI上输入DateTime值的视觉控制。请更好地查看您的代码，然后查看该控件的命名。然后用该字符串替换DTP_RentedDate。