asp.net 对数据库表增加，删除，编辑更新修改

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

 public partial class _Default : System.Web.UI.Page
 {
     private string constr = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;

     SqlHelper helper = new SqlHelper();
     protected void Page_Load(object sender, EventArgs e)
     {
         if (!Page.IsPostBack)
         {
             using (SqlConnection conn = new SqlConnection(constr))
             {

                  SqlDataAdapter ad = new SqlDataAdapter("select * from tbuser", conn);
                  SqlCommandBuilder builder = new SqlCommandBuilder(ad);
                  DataTable dt = new DataTable();
                  ad.Fill(dt);
                  this.GridView1.DataSource = dt;
                  this.DataBind();
             }
         }
     }

     private void userlistbind()
     {
         GridView1.DataSource = helper.SelectSqlReturnDataset("select id, username as '用户名',birthday  as '生日', '部门号'=(select departmentname from tbdepartment where tbdepartment.departmentid=tbUser.departmentid) from tbUser").Tables[];
     }
     protected void btnAdd_Click(object sender, EventArgs e)
     {

         string sql = "insert into tbUser(username,birthday,departmentid) values('" + txtUserName.Text + "','" + txtBirthday.Text + "'," + ddlDepartment.SelectedValue.ToString() + ")";
         int count = helper.ExecuteReturnInt(sql, null, System.Data.CommandType.Text);
         if (count != )
         {
             userlistbind();
             Response.Write("<script>alert('数据添加成功！')</script>");
             txtBirthday.Text = "";
             txtUserName.Text = "";

             GridView1.DataBind();
         }
     }
     protected void GridView1_RowCommand(object sender, GridViewCommandEventArgs e)
     {

     }
     protected void bind()
     {
         SqlConnection myconn = new SqlConnection(constr);
         myconn.Open();
         string sql = "select id,username 用户名,birthday 生日,departmentid 部门号 from tbUser";
         SqlDataAdapter myda = new SqlDataAdapter(sql, myconn);
         DataSet myds = new DataSet();
         myda.Fill(myds);
         GridView1.DataSource = myds;
         GridView1.DataKeyNames = new string[] { "id" };
         GridView1.DataBind();
         myda.Dispose();
         myds.Dispose();
         myconn.Close();
     }

     protected void GridView1_RowEditing(object sender, GridViewEditEventArgs e)
     {
         GridView1.EditIndex = e.NewEditIndex;
         this.bind();
     }
     protected void GridView1_RowUpdating(object sender, GridViewUpdateEventArgs e)
     {

         int id = Convert.ToInt32(GridView1.DataKeys[e.RowIndex].Value.ToString());
         string name = ((TextBox)(GridView1.Rows[e.RowIndex].Cells[].Controls[])).Text.ToString();
         string birthday = ((TextBox)(GridView1.Rows[e.RowIndex].Cells[].Controls[])).Text.ToString();
         string department = ((TextBox)(GridView1.Rows[e.RowIndex].Cells[].Controls[])).Text.ToString();
         string sql = "update tbUser set username='" + name + "',birthday='"+birthday+"',departmentid="+department+" where id=" + id + "";
         SqlConnection myconn = new SqlConnection(constr);
         myconn.Open();
         SqlCommand mycmd = new SqlCommand(sql, myconn);
         mycmd.ExecuteNonQuery();
         mycmd.Dispose();
         myconn.Close();
         GridView1.EditIndex = -;
         this.bind();
     }
     protected void GridView1_RowCancelingEdit(object sender, GridViewCancelEditEventArgs e)
     {
         GridView1.EditIndex = -;
         this.bind();
     }
     protected void GridView1_RowDeleting(object sender, GridViewDeleteEventArgs e)
     {
         int id = Convert.ToInt32(GridView1.DataKeys[e.RowIndex].Value.ToString());
         string sql = "delete from tbUser where id=" + id + "";
         SqlConnection myconn = new SqlConnection(constr);
         myconn.Open();
         SqlCommand mycmd = new SqlCommand(sql, myconn);
         mycmd.ExecuteNonQuery();
         mycmd.Dispose();
         myconn.Close();
         GridView1.EditIndex = -;
         this.bind();
     }
     protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)
     {

         if (e.Row.RowType == DataControlRowType.DataRow)
         {
             ((LinkButton)e.Row.Cells[].Controls[]).Attributes.Add("onclick", "return confirm('确定要删除吗')");
         }
     }
 }

web.config

<configuration>
<connectionStrings>
<add name="constr" connectionString="server=.\sqlexpress;database=db2016;uid=sa;pwd=123;" />
<add name="db2016ConnectionString" connectionString="Data Source=.\sqlexpress;Initial Catalog=db2016;Persist Security Info=True;User ID=sa;Password=123"
providerName="System.Data.SqlClient" />
</connectionStrings>
<system.web>
<compilation debug="true" targetFramework="4.0" />
</system.web>

</configuration>

GridView的datakeyname属性 设为id

数据库表

create table tbUser

(
id int primary key identity(1,1),
username nvarchar(20),
userpass varbinary(128),
birthday datetime,
departmentid int foreign key references tbdepartment(departmentid)
)