winform中利用ado.net实现对单表的增删改查的详细例子，具体如下：
1.前言：
运行环境：VS2013+SQL2008+Windows10
程序界面预览：
使用的主要控件：dataGridview和menuStrip等。
2.功能具体介绍：
1.首先，我们要先实现基本的数据操作，增删改查这几个操作。
（1）先定义一个数据库操作的公共类：
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Data;
using System.Configuration;
using System.Data.SqlClient;
using System.Security.Cryptography;
namespace Data
{
class SqlDesigner
{
private static string connStr = ConfigurationManager.ConnectionStrings["data"].ConnectionString;
/// <summary>
/// 返回受影响的数据行数
/// </summary>
/// <param name="sql"></param>
/// <returns></returns>
public static int ExecuteNoQuery(string sql)
{
using (SqlConnection conn=new SqlConnection(connStr))
{
conn.Open();
using (SqlCommand cmd=conn.CreateCommand())
{
cmd.CommandText = sql;
return cmd.ExecuteNonQuery();
}
}
}
/// <summary>
/// 返回一个数据集
/// </summary>
/// <param name="sql"></param>
/// <returns></returns>
public static DataSet ExecuteDataSet(string sql)
{
using (SqlConnection xonn=new SqlConnection(connStr))
{
xonn.Open();
using (SqlCommand cmd = xonn.CreateCommand())
{
cmd.CommandText = sql;
SqlDataAdapter adapter = new SqlDataAdapter(cmd);
DataSet dataset = new DataSet();
adapter.Fill(dataset);
return dataset;
}
}
}
public static object ExecuteScalar(string sql)
{
using (SqlConnection conn=new SqlConnection(connStr))
{
conn.Open();
using (SqlCommand cmd=conn.CreateCommand())
{
cmd.CommandText = sql;
return cmd.ExecuteScalar();
}
}
}
/// <summary>
/// md5加密
/// </summary>
/// <param name="strPwd"></param>
/// <returns></returns>
public static string GetMD5(string strPwd)
{
string pwd = "";
//实例化一个md5对象
MD5 md5 = MD5.Create();
// 加密后是一个字节类型的数组
byte[] s = md5.ComputeHash(Encoding.UTF8.GetBytes(strPwd));
//翻转生成的MD5码
s.Reverse();
//通过使用循环，将字节类型的数组转换为字符串，此字符串是常规字符格式化所得
//只取MD5码的一部分，这样恶意访问者无法知道取的是哪几位
for (int i = 3; i < s.Length - 1; i++)
{
//将得到的字符串使用十六进制类型格式。格式后的字符是小写的字母，如果使用大写（X）则格式后的字符是大写字符
//进一步对生成的MD5码做一些改造
pwd = pwd + (s[i] < 198 ? s[i] + 28 : s[i]).ToString("X");
}
return pwd;
}
}
}
（2）运用建立的公共类，进行数据库的操作：
a.数据查询：
ds = SqlDesigner.ExecuteDataSet("select * from dtuser");
dt = ds.Tables[0];
dataGridView1.DataSource = dt;
b.数据添加
i = SqlDesigner.ExecuteNoQuery("insert into dtuser(uid,uname,pwd,uflag)values('" + textBox1.Text + "','" + textBox2.Text + "','" +textBox3.Text+ "','" + textBox4.Text + "')");
c.数据删除
string currentIndex = dataGridView1.CurrentRow.Cells[0].Value.ToString();
i = SqlDesigner.ExecuteNoQuery("delete from dtuser where uid='" + currentIndex + "'");
d.数据修改
i = SqlDesigner.ExecuteNoQuery("update dtrole set rname='" + textBox2.Text + "',flag='" + textBox3.Text + "'where rid='" + textBox1.Text + "'");
e.一些细节
这里，我们修改一下添加数据，让添加的数据变成字符串的形式，也就是加密操作：
string str = SqlDesigner.GetMD5(textBox3.Text.Trim());
i = SqlDesigner.ExecuteNoQuery("insert into dtuser(uid,uname,pwd,uflag)values('" + textBox1.Text + "','" + textBox2.Text + "','" + str + "','" + textBox4.Text + "')");
（3）dataGridView控件：
//绑定数据源 dataGridView1.DataSource = dt; //自动适应列宽 dataGridView1.Columns[1].AutoSizeMode = DataGridViewAutoSizeColumnMode.AllCells;
3.代码仅供参考：
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace Data
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
DataSet ds = new DataSet();
DataTable dt = new DataTable();
private void TextBoxNull()
{
textBox1.Text = "";
textBox2.Text = "";
textBox3.Text = "";
textBox4.Text = "";
}
private void 用户ToolStripMenuItem_Click(object sender, EventArgs e)
{
TextBoxNull();
ds = SqlDesigner.ExecuteDataSet("select * from dtuser");
dt = ds.Tables[0];
dataGridView1.DataSource = dt;
labelshow();
}
private void 角色ToolStripMenuItem_Click(object sender, EventArgs e)
{
TextBoxNull();
ds = SqlDesigner.ExecuteDataSet("select *from dtrole");
dt = ds.Tables[0];
dataGridView1.DataSource = dt;
label4.Text = "None";
textBox4.Text = "None";
labelshow();
}
private void 对象ToolStripMenuItem_Click(object sender, EventArgs e)
{
TextBoxNull();
ds = SqlDesigner.ExecuteDataSet("select * from dtfunction");
dt = ds.Tables[0];
dataGridView1.DataSource = dt;
labelshow();
}
private void 帮助ToolStripMenuItem_Click(object sender, EventArgs e)
{
TextBoxNull();
ds = SqlDesigner.ExecuteDataSet("select * from help");
dt = ds.Tables[0];
dataGridView1.DataSource = dt;
dataGridView1.Columns[1].AutoSizeMode = DataGridViewAutoSizeColumnMode.AllCells;
}
//双击dataGridView1
private void dataGridView1_CellDoubleClick(object sender, DataGridViewCellEventArgs e)
{
string index = dataGridView1.CurrentRow.Cells[0].Value.ToString();
if (label1.Text == "uid")
{
ds = SqlDesigner.ExecuteDataSet("select *from dtuser where uid='" + index + "'");
dt = ds.Tables[0];
DataRow row = dt.Rows[0];
textBox1.Text = row["uid"].ToString();
textBox2.Text = row["uname"].ToString();
textBox3.Text = row["pwd"].ToString();
textBox4.Text = row["uflag"].ToString();
}
if (label1.Text == "rid")
{
ds = SqlDesigner.ExecuteDataSet("select *from dtrole where rid='" + index + "'");
dt = ds.Tables[0];
DataRow row = dt.Rows[0];
textBox1.Text = row["rid"].ToString();
textBox2.Text = row["rname"].ToString();
textBox3.Text = row["flag"].ToString();
textBox4.Text = "None";
}
if (label1.Text == "fid")
{
ds = SqlDesigner.ExecuteDataSet("select *from dtfunction where fid='" + index + "'");
dt = ds.Tables[0];
DataRow row = dt.Rows[0];
textBox1.Text = row["fid"].ToString();
textBox2.Text = row["fname"].ToString();
textBox3.Text = row["flag"].ToString();
textBox4.Text = row["uflag"].ToString();
}
}
private void labelshow()
{
label1.Text = dataGridView1.Columns[0].HeaderText;
label2.Text = dataGridView1.Columns[1].HeaderText;
label3.Text = dataGridView1.Columns[2].HeaderText;
try
{
label4.Text = dataGridView1.Columns[3].HeaderText;
}
catch (Exception)
{
label4.Text = "None";
}
}
private void btn_add_Click(object sender, EventArgs e)
{
int i = 0;
if (label1.Text=="uid")
{
string str = SqlDesigner.GetMD5(textBox3.Text.Trim());
i = SqlDesigner.ExecuteNoQuery("insert into dtuser(uid,uname,pwd,uflag)values('" + textBox1.Text + "','" + textBox2.Text + "','" + str + "','" + textBox4.Text + "')");
}
else if (label1.Text == "rid")
{
i = SqlDesigner.ExecuteNoQuery("insert into dtrole(rid,rname,flag)values('" + textBox1.Text + "','" + textBox2.Text + "','" + textBox3.Text + "')");
}
else
{
try
{
i = SqlDesigner.ExecuteNoQuery("insert into dtfunction(fid,rid,uid,uflag)values('" + textBox1.Text + "','" + textBox2.Text + "','" + textBox3.Text + "','" + textBox4.Text + "')");
}
catch (Exception)
{
MessageBox.Show("添加失败");
}
}
if (i > 0)
{
MessageBox.Show("添加成功");
}
else
{
MessageBox.Show("添加失败");
}
}
private void btn_del_Click(object sender, EventArgs e)
{
int i = 0;
string currentIndex = dataGridView1.CurrentRow.Cells[0].Value.ToString();
if (label1.Text=="uid")
{
i = SqlDesigner.ExecuteNoQuery("delete from dtuser where uid='" + currentIndex + "'");
}
else if (label1.Text=="fid")
{
i = SqlDesigner.ExecuteNoQuery("delete from dtfunction where fid='" + currentIndex + "'");
}
else
{
i = SqlDesigner.ExecuteNoQuery("delete from dtrole where rid='" + currentIndex + "'");
}
if (i > 0)
{
MessageBox.Show("删除成功");
}
else
{
MessageBox.Show("删除失败");
}
}
private void btn_update_Click(object sender, EventArgs e)
{
int i = 0;
if (label1.Text == "rid")
{
i = SqlDesigner.ExecuteNoQuery("update dtrole set rname='" + textBox2.Text + "',flag='" + textBox3.Text + "'where rid='" + textBox1.Text + "'");
}
if (label1.Text == "uid")
{
i = SqlDesigner.ExecuteNoQuery("update dtuser set uname='" + textBox2.Text + "',pwd='" + textBox3.Text + "',uflag='" + textBox4.Text + "'where uid='" + textBox1.Text + "'");
}
if (label1.Text=="fid")
{
i = SqlDesigner.ExecuteNoQuery("update dtfunction set rid='" + textBox2.Text + "',uid='" + textBox3.Text + "',uflag='" + textBox4.Text + "'where fid='" + textBox1.Text + "'");
}
if (i > 0)
{
MessageBox.Show("Succeed！");
}
else
{
MessageBox.Show("Failed！");
}
}
}
}
