ADO.NET之数据插入、修改、删除、查询操作

背景：VisualStudio2005；

对数据库进行查询、插入、修改、删除操作；

使用GridView控件显示数据；

实现：

数据库设计

create database db_user
go
use db_user
go
create table tb_user
( pID varchar(10) primary key,
pName varchar(20) not null,
pSex varchar(2) not null
)
go
insert into tb_user values('1','admin','男')
go
select * from tb_user
go

界面

代码

html:

<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

后台:

person.cs:

public class person
{
    //定义person对象的三个属性字段
    public string pID;
    public string pName;
    public string pSex;
    public person()
{
  //
  // TODO: 在此处添加构造函数逻辑
  //
}
}

personOperate.cs:

using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Data.SqlClient;

/// <summary>
/// operate 的摘要说明，所有操作类
/// </summary>
public class personOperate
{
public personOperate()
{
  //
  // TODO: 在此处添加构造函数逻辑
  //
}
    public static SqlConnection createCon()
    {
        return new SqlConnection("server=localhost\\sqlexpress;database=db_user;uid=sa;pwd=hello");
    }

    //根据员工工号 pID查询数据库是否已经存在同名记录
    public static bool findPerson( string pID)
    {
        SqlConnection con = personOperate.createCon();
        con.Open();
        SqlCommand cmd = new SqlCommand("select count(*) from tb_user where pID='" + pID + "'", con);
        //用count获取：返回查询所返回的结果集中的第一行第一列；如果大于0表示存在记录；反之则不存在
        int count = Convert.ToInt32(cmd.ExecuteScalar());
        if (count > 0)
        {
            return true;
        }
        else
        {
            return false;
        }
    }

    //显示所有员工信息
    public static DataTable selectAll()
    {
        SqlConnection con = personOperate.createCon();
        //SqlDataApapter表示用于填充DataSet和更新SQL Server数据库的一组数据命令和一个数据库连接
        SqlDataAdapter sda = new SqlDataAdapter();
        //（获取或）设置一个T_SQL语句或存储过程，用于在数据源中选择记录
        sda.SelectCommand = new SqlCommand("select * from tb_user", con);
        //DataSet表示数据在内存中的缓存；初始化DataSet类的新实例
        DataSet ds = new DataSet();
        //使用sda.Fill（）方法填充ds，并创建一个名为“user"的DataTable对象,将数据存放在表中
        sda.Fill(ds, "user");
        //（获取或）设置在DataSet中的表的集合
        //获取数据集中的数据表
        return ds.Tables["user"];

}

   //添加员工数据，添加时检查员工工号字段pID是否已经存在
    public static bool addPerson(person p)
    {
        try
        {
            SqlConnection con = personOperate.createCon();
            con.Open();
            SqlCommand cmd = new SqlCommand("insert into tb_user values(@pID,@pName,@pSex)", con);
            SqlParameter para = new SqlParameter("@pID", SqlDbType.VarChar, 10);
            para.Value = p.pID;
            cmd.Parameters.Add(para);
            para = new SqlParameter("@pName", SqlDbType.VarChar, 20);
            para.Value = p.pName;
            cmd.Parameters.Add(para);
            para = new SqlParameter("@pSex", SqlDbType.VarChar, 2);
            para.Value = p.pSex;
            cmd.Parameters.Add(para);
            cmd.ExecuteNonQuery();
            return true;
        }
        catch (Exception e)
        {
            return false;
        }
    }

    //根据员工工号pID删除员工数据
    public static bool delPerson(string pID)
    {
        try
        {
            SqlConnection con = personOperate.createCon();
            con.Open();
            //表示要对SQL Server数据库执行一个T_SQL语句或存储过程，在此使用参数
            SqlCommand cmd = new SqlCommand("delete from tb_user where pID='" + @pID + "'", con);
            //表示SqlCommand的参数（参数名称，数据类型，大小）
            SqlParameter para = new SqlParameter("@pID", SqlDbType.VarChar, 10);
            //（获取或）设置参数的值
            para.Value = pID;
            //将制定的SqlParameter对象添加到SqlParameterCollection中
            cmd.Parameters.Add(para);
            //对连接执行T_SQL语句并返回受影响的行数
            cmd.ExecuteNonQuery();
            return true;

        }
        catch (Exception e)
        {
            return false;
        }
    }

    //根据员工工号pID修改员工数据
    public static bool editPerson(person p)
    {
        try
        {
            SqlConnection con = personOperate.createCon();
            con.Open();
            SqlCommand cmd = new SqlCommand("update tb_user set pName='"+p.pName+ "',pSex='" + p.pSex + "' where pID='" +p.pID+"'", con);

            cmd.ExecuteNonQuery();
            return true;
        }
        catch (Exception eedit)
        {
            return false;
        }
    }

    //根据条件模糊查询用户信息
    public static DataTable selectPerson(string sql)
    {

        SqlConnection con = personOperate.createCon();
        con.Open();
        SqlDataAdapter sda = new SqlDataAdapter();
        sda.SelectCommand = new SqlCommand(sql, con);
        DataSet ds = new DataSet();
        sda.Fill(ds, "user");
        return ds.Tables["user"];
    }
}

Default.aspx:

public partial class _Default : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        if (!IsPostBack)
        {
            //初始化页面时,读取全部用户信息
            this.fillGV();
        }
    }

    protected void CustomValidator1_ServerValidate(object source, ServerValidateEventArgs args)
    {
       //获取需自定义验证控件验证的值
        string pID = args.Value;
        //调用personOperate.findPerson()函数
        if(personOperate.findPerson(pID))
        {
            args.IsValid=false;
        }
        else
        {
            args.IsValid=true;
        }
    }

    //将GridView1数据源设置为DataTable表数据
    private void fillGV()
    {
        this.GridView1.DataSource=personOperate.selectAll();
        this.GridView1.DataBind();

}

    protected void btnAdd_Click(object sender, EventArgs e)
    {
       //如果页面通过验证，则引发添加数据的按钮事件
        if (this.IsValid)
        {
            //实例化person对象
            person p = new person();
            p.pID = this.txtPID.Text;
            p.pName = this.txtName.Text;
            if (this.rbtMale.Checked)
            {
                p.pSex = "男";
            }
            else
            {
                p.pSex = "女";
            }
            //如果用户不存在则调用personOperate.delPerson()方法进行用户信息添加
            if (personOperate.addPerson(p))
            {
                this.lblMessage.Text = "插入成功！";
                this.fillGV();

            }
            else
            {
                this.lblMessage.Text = "插入失败！";
            }
        }
    }

    protected void btnDelete_Click(object sender, EventArgs e)
    {
          //获取用户的工号字段值pID,并调用personOperate.delPerson(）方法删除指定用户信息
            string pID = this.txtPID.Text;
            if (personOperate.delPerson(pID))
            {
                this.lblMessage.Text = "删除成功！";
                this.fillGV();
            }
            else
            {
                this.lblMessage.Text = "删除失败！";
            }

    }

    //根据员工工号修改员工信息
    protected void btnEdit_Click(object sender, EventArgs e)
    {

            person p = new person();
            p.pID = this.txtPID.Text;
            p.pName = this.txtName.Text;
            if (this.rbtMale.Checked)
            {
                p.pSex = "男";
            }
            else
            {
                p.pSex = "女";
            }
            if (personOperate.editPerson(p))
            {
                this.lblMessage.Text = "修改成功！";
                this.fillGV();

            }
            else
            {
                this.lblMessage.Text = "修改失败！";
            }

    }

    protected void btnSelect_Click(object sender, EventArgs e)
    {
        //初始设置查询字符串，使用"where 1=1"
        string sqlQuery = "select * from tb_user where 1=1 ";
        if (this.chkPID.Checked)
        {
            sqlQuery = sqlQuery + " and"+" pID like '%"+ this.txtPID.Text +"%'";

        }
        if (this.chkPName.Checked)
        {
            sqlQuery = sqlQuery + " and" + " pName like '%" + this.txtName.Text + "%'";

        }
        if (this.chkPSex.Checked && this.rbtMale.Checked)
        {
            sqlQuery += " and" + " pSex='" + "男" + "'";
        }
        if (this.chkPSex.Checked && this.rbtFemale.Checked)
        {
            sqlQuery += " and" + " pSex='" + "女" + "'";
        }
        //SqlConnection con = personOperate.createCon();
        //con.Open();
        //SqlDataAdapter sda = new SqlDataAdapter();
        //sda.SelectCommand = new SqlCommand(sqlQuery, con);
        //DataSet ds = new DataSet();
        //sda.Fill(ds, "user");
        //this.GridView1.DataSource = ds.Tables["user"];
        //this.GridView1.DataBind();
        this.GridView1.DataSource = personOperate.selectPerson(sqlQuery);
        this.GridView1.DataBind();

}

}