C# 从文本字段插入到表-空字段

C# 从文本字段插入到表-空字段,c#,asp.net,sql-server-express,C#,Asp.net,Sql Server Express,我有一些问题:下面的代码用新行更新表,但此行中的所有字段都是空的。我想将文本字段中的输入数据放入表成员的新行中 using System; using System.Collections.Generic; using System.Linq; using System.Web; using System.Web.UI; using System.Web.UI.WebControls; using System.Data; using System.Data.SqlClient; using S

我有一些问题:下面的代码用新行更新表,但此行中的所有字段都是空的。我想将文本字段中的输入数据放入表成员的新行中

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Data;
using System.Data.SqlClient;
using System.Web.Configuration;

public partial class Default4 : System.Web.UI.Page
{
   protected void Page_Load(object sender, EventArgs e)
    {
        txtFirstName.Text = "";
        txtLastName.Text = "";
        txtAdress.Text = "";
        txtResidence.Text = "";
        txtEmail.Text = "";
    }
    protected void btnRegister_Click(object sender, EventArgs e)
    {
        SqlConnection con = new SqlConnection(
            WebConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString);
        SqlCommand cmd = new SqlCommand("INSERT INTO Members(FirstName, LastName, Adress, Residence, Email) VALUES (@txtFirstName, @txtLastName, @txtAdress, @txtResidence, @txtEmail)", con);
        cmd.Parameters.AddWithValue("@txtFirstName", txtFirstName.Text);
        cmd.Parameters.AddWithValue("@txtLastName", txtLastName.Text);
        cmd.Parameters.AddWithValue("@txtAdress", txtAdress.Text);
        cmd.Parameters.AddWithValue("@txtResidence", txtResidence.Text);
        cmd.Parameters.AddWithValue("@txtEmail", txtEmail.Text);

        try
        {
            con.Open();
            cmd.ExecuteNonQuery();

            lblConfirm.Text = "Database updated, insert confirmed!";

            txtFirstName.Text = "";
            txtLastName.Text = "";
            txtAdress.Text = "";
            txtResidence.Text = "";
            txtEmail.Text = "";
        }
        finally
        {
            con.Close();
        }
    }
}
如果我更改此行:

SqlCommand cmd = new SqlCommand("INSERT INTO Members(FirstName, LastName, Adress, Residence, Email) VALUES (@txtFirstName, @txtLastName, @txtAdress, @txtResidence, @txtEmail)", con);
对这样的事情:

SqlCommand cmd = new SqlCommand("INSERT INTO Members(FirstName, LastName, Adress, Residence, Email) VALUES ('@txtFirstName', '@txtLastName', @txtAdress, @txtResidence, @txtEmail)", con);
它将打印出一行,其中包含如下字段: |@txtLastName |@txtLastName |[Empty]|[Empty]|[Empty]|


任何帮助都会很好,谢谢

每次按注册按钮时,
页面加载将执行,清空文本框,然后执行
btnRegister\u单击
。此时,您的文本框为空

您需要在页面加载事件中添加检查

   if(!IsPostBack)
   {
      ... // code to empty the textboxes
   }

问题出在这里

    try
    {
        con.Open();
        cmd.ExecuteNonQuery();

        lblConfirm.Text = "Database updated, insert confirmed!";

        txtFirstName.Text = "";
        txtLastName.Text = "";
        txtAdress.Text = "";
        txtResidence.Text = "";
        txtEmail.Text = "";
    }
^^^^^^重置此处的所有字段不会有任何区别。它将在每次回发后发生

试试这个

if(!IsPostBack)
   {
            txtFirstName.Text = "";
            txtLastName.Text = "";
            txtAdress.Text = "";
            txtResidence.Text = "";
            txtEmail.Text = "";
   }
因此,用户输入不会在单击按钮时重置为无

这里有更好的方法来实现你的目标