如何使用C#将SQL数据库中的值获取到文本框中？

Question

我正在创建一个预订管理系统,我在尝试从SQL数据库中获取数据并插入到我的应用程序的一组文本框中时遇到问题.

我想在DataGridView中显示单击按钮时的客户详细信息,但是当我单击该按钮时,应用程序会抛出异常并显示以下错误消息;

没有数据时无效尝试读取.

我附上了我要查看客户详细信息的屏幕截图,以及按钮的代码,最终会在相应的文本框中显示客户详细信息.任何帮助将不胜感激!

    SqlConnection sc = new SqlConnection("Data Source=localhost;Initial Catalog=LoginScreen;Integrated Security=True");
        SqlCommand com = new SqlCommand();
        com.Connection = sc;
        sc.Open();
        SqlDataReader read = (null);
        com.CommandText = ("select * from Pending_Tasks");
        read = com.ExecuteReader();
        CustID.Text = (read["Customer_ID"].ToString());
        CustName.Text = (read["Customer_Name"].ToString());
        Add1.Text = (read["Address_1"].ToString());
        Add2.Text = (read["Address_2"].ToString());
        PostBox.Text = (read["Postcode"].ToString());
        PassBox.Text = (read["Password"].ToString());
        DatBox.Text = (read["Data_Important"].ToString());
        LanNumb.Text = (read["Landline"].ToString());
        MobNumber.Text = (read["Mobile"].ToString());
        FaultRep.Text = (read["Fault_Report"].ToString());
        sc.Close();

Answer 1

reader.Read()您的代码中缺少该行.你应该添加它.它是实际从数据库中读取数据的函数:

string conString = "Data Source=localhost;Initial Catalog=LoginScreen;Integrated Security=True";
SqlConnection con = new SqlConnection(conString);

string selectSql = "select * from Pending_Tasks";
SqlCommand com = new SqlCommand(selectSql, con);

try
{
    con.Open();

    using (SqlDataReader read = cmd.ExecuteReader())
    {
        while(reader.Read())
        {
            CustID.Text = (read["Customer_ID"].ToString());
            CustName.Text = (read["Customer_Name"].ToString());
            Add1.Text = (read["Address_1"].ToString());
            Add2.Text = (read["Address_2"].ToString());
            PostBox.Text = (read["Postcode"].ToString());
            PassBox.Text = (read["Password"].ToString());
            DatBox.Text = (read["Data_Important"].ToString());
            LanNumb.Text = (read["Landline"].ToString());
            MobNumber.Text = (read["Mobile"].ToString());
            FaultRep.Text = (read["Fault_Report"].ToString());
        }
    }
}
finally
{
    con.Close();
}

编辑:此代码工作假设您要将最后一条记录写入文本框.如果要应用不同的方案,例如从数据库中读取所有记录并在单击Next按钮时更改texbox中的数据,则应创建并使用自己的模型,或者可以将数据存储在DataTable中如果你愿意,请稍后再提及.