C# System.InvalidCastException：尝试在C中使用实体框架向SQL数据库添加对象时#

我正在尝试使用C#中的实体框架向SQL数据库添加对象。数据来自文本框和日期选择器控件的组合。我猜这是我如何解析数据的一个问题，但是错误对我来说似乎很模糊。如有任何建议，将不胜感激

下面是将数据添加到数据库的代码

private void new_btn_Click(object sender, RoutedEventArgs e)
{
        var load = new Load
        {
            pro_num = pro_txt.Text,
            quote_num = quote_txt.Text,
            ref_num = ref_txt.Text,
            weight = Convert.ToDouble(weight_txt.Text),
            pieces = Convert.ToInt32(pieces_txt.Text),
            commodity = commodity_txt.Text,
            mileage = Convert.ToDouble(mileage_txt.Text),
            carrier_rate = Convert.ToDecimal(carrierRate_txt.Text),
            customer_rate = Convert.ToDecimal(customerRate_txt.Text),
            pick_appointment = pickDate_picker.SelectedDate,
            drop_appointment = dropDate_picker.SelectedDate,
            driver_id = Convert.ToInt32(driver_txt),
            dispatch_id = Convert.ToInt32(dispatch_txt),
            customer_id = Convert.ToInt32(customer_txt),
            broker_id = Convert.ToInt32(broker_txt),
        };

        HotloadModel.Loads.Add(load);
        HotloadModel.SaveChangesAsync();
}

以下是EF实体类的代码：

public partial class Load
{
    public int bol_num { get; set; }
    public string pro_num { get; set; }
    public string quote_num { get; set; }
    public string ref_num { get; set; }
    public Nullable<double> weight { get; set; }
    public Nullable<int> pieces { get; set; }
    public string commodity { get; set; }
    public Nullable<double> mileage { get; set; }
    public Nullable<decimal> carrier_rate { get; set; }
    public Nullable<decimal> customer_rate { get; set; }
    public Nullable<System.DateTime> pick_appointment { get; set; }
    public Nullable<System.DateTime> drop_appointment { get; set; }
    public Nullable<int> driver_id { get; set; }
    public Nullable<int> dispatch_id { get; set; }
    public Nullable<int> customer_id { get; set; }
    public Nullable<int> broker_id { get; set; }
}

---

在盯着代码看了15分钟后，我意识到我忽略了在这些行中指定.Text属性

        driver_id = Convert.ToInt32(driver_txt),
        dispatch_id = Convert.ToInt32(dispatch_txt),
        customer_id = Convert.ToInt32(customer_txt),
        broker_id = Convert.ToInt32(broker_txt),

---

此外，我还使用了一篇相关SO帖子中的链接来验证我是否正确转换了值

我认为这些字段也在文本框中，也许您必须获得文本值：

driver_id = Convert.ToInt32(driver_txt.Text),
dispatch_id = Convert.ToInt32(dispatch_txt.Text),
customer_id = Convert.ToInt32(customer_txt.Text),
broker_id = Convert.ToInt32(broker_txt.Text),

---

下次阅读异常：“无法将'System.Windows.Forms.TextBox'类型的对象强制转换为'System.IConvertible'类型”否，我获取文本属性，例如：

driver\u txt.text

，因为您在上一条注释中写了一个异常。在您的示例中，您尝试从

driver\u txt

而不是

driver\u txt.Text

获取int32值。