下面的示例中，通过一个程序，演示使用DataRowState、AcceptChanges、RejectChanges，实现DataGridView数据的增、删、改。
一、界面设计
二、代码实现
1 using System;
2 using System.Collections.Generic;
3 using System.ComponentModel;
4 using System.Data;
5 using System.Drawing;
6 using System.Linq;
7 using System.Text;
8 using System.Threading.Tasks;
9 using System.Windows.Forms;
10 using System.Data;
11 using System.Data.SqlClient;
12 using System.Configuration;
13
14 namespace DataRowStateDemo
15 {
16 public partial class FrmMain : Form
17 {
18 public FrmMain()
19 {
20 InitializeComponent();
21 }
22
23 //连接字符串
24 string strConn = ConfigurationManager.ConnectionStrings["DbConn"].ConnectionString;
25
26 /// <summary>
27 /// 加载
28 /// </summary>
29 /// <param name="sender"></param>
30 /// <param name="e"></param>
31 private void btn_LoadData_Click(object sender, EventArgs e)
32 {
33 Initdgv();
34 this.btn_Add.Visible = false;
35 }
36
37 /// <summary>
38 /// 初始化DataGridView
39 /// </summary>
40 private void Initdgv()
41 {
42 SqlConnection conn = new SqlConnection(strConn);
43 string strSQL = "select * from Users";
44 SqlCommand cmd = new SqlCommand(strSQL, conn);
45 SqlDataAdapter adapter = new SqlDataAdapter(cmd);
46 DataSet dsDgv = new System.Data.DataSet();
47 try
48 {
49 conn.Open();
50 //填充数据
51 adapter.Fill(dsDgv);
52
53 this.dgv_Demo.DataSource = dsDgv.Tables[0];
54 //不显示最后的空行
55 this.dgv_Demo.AllowUserToAddRows = false;
56 // 设置第一列只读
57 this.dgv_Demo.Columns[0].ReadOnly = true;
58 }
59 catch (Exception ex)
60 { }
61 finally
62 {
63 conn.Close();
64 }
65 }
66
67 /// <summary>
68 /// 编辑
69 /// </summary>
70 /// <param name="sender"></param>
71 /// <param name="e"></param>
72 private void btn_Edit_Click(object sender, EventArgs e)
73 {
74 this.dgv_Demo.AllowUserToAddRows = true;
75 }
76
77 /// <summary>
78 /// 保存
79 /// </summary>
80 /// <param name="sender"></param>
81 /// <param name="e"></param>
82 private void btn_Save_Click(object sender, EventArgs e)
83 {
84 DataTable dtCopy = this.dgv_Demo.DataSource as DataTable;
85 DataSet dsUsers = new DataSet();
86
87 //产生与表Users结构相同的空表
88 DataTable dtAdd = GetEmptyTable();
89 DataTable dtEdit = GetEmptyTable();
90 DataTable dtDel = GetEmptyTable();
91
92 //根据DataRowState的状态获取新增、修改、删除的表数据
93 dtAdd = dtCopy.GetChanges(DataRowState.Added);
94 dtEdit = dtCopy.GetChanges(DataRowState.Modified);
95 dtDel = dtCopy.GetChanges(DataRowState.Deleted);
96
97 //新增
98 if (dtAdd != null)
99 {
100 dtAdd.TableName = "Added";
101 dsUsers.Tables.Add(dtAdd);
102 }
103 //修改
104 if (dtEdit != null)
105 {
106 dtEdit.TableName = "Edit";
107 dsUsers.Tables.Add(dtEdit);
108 }
109 //删除
110 if (dtDel != null)
111 {
112 dtDel.TableName = "Del";
113 dtDel.RejectChanges();
114 dsUsers.Tables.Add(dtDel);
115 }
116 //保存数据
117 if (SaveUser(dsUsers))
118 {
119 MessageBox.Show("保存成功!");
120 //重新加载数据
121 Initdgv();
122 }
123 else
124 {
125 MessageBox.Show("保存失败!");
126 }
127 }
128
129 /// <summary>
130 /// 根据表结构产生空表
131 /// </summary>
132 /// <returns></returns>
133 private DataTable GetEmptyTable()
134 {
135 DataTable dtTable = new DataTable("Users");
136 //使用集合初始化器添加列
137 dtTable.Columns.AddRange(new DataColumn[]{
138 new DataColumn("UserID",typeof(Int32)),
139 new DataColumn("UserName",typeof(string)),
140 new DataColumn("Password",typeof(string)),
141 new DataColumn("Sex",typeof(Char)),
142 new DataColumn("Birthday",typeof(DateTime))
143 });
144 return dtTable;
145 }
146
147 /// <summary>
148 /// 保存数据
149 /// </summary>
150 /// <param name="ds"></param>
151 /// <returns></returns>
152 private bool SaveUser(DataSet ds)
153 {
154 bool tf = false;
155 //新增
156 if (ds.Tables["Added"] != null)
157 {
158 foreach (DataRow dr in ds.Tables["Added"].Rows)
159 {
160 tf= InsertUser(dr);
161 }
162 }
163 //修改
164 if (ds.Tables["Edit"] != null)
165 {
166 foreach (DataRow dr in ds.Tables["Edit"].Rows)
167 {
168 tf = UpdateUser(dr);
169 }
170 }
171 //删除
172 if (ds.Tables["Del"] != null)
173 {
174 foreach (DataRow dr in ds.Tables["Del"].Rows)
175 {
176 tf = DeleteUser(dr);
177 }
178 }
179 return tf;
180 }
181
182 /// <summary>
183 /// 数据库增加
184 /// </summary>
185 /// <param name="drDataRow"></param>
186 /// <returns></returns>
187 private bool InsertUser(DataRow drDataRow)
188 {
189 string strSQL = string.Format(@"insert into users values(‘{0}‘,‘{1}‘,‘{2}‘,‘{3}‘)", drDataRow["UserName"].ToString(), drDataRow["Password"].ToString(), drDataRow["Sex"].ToString(), drDataRow["Birthday"].ToString());
190 return ExecuteSQL(strSQL);
191 }
192
193 /// <summary>
194 /// 数据库删除
195 /// </summary>
196 /// <param name="drDataRow"></param>
197 /// <returns></returns>
198 private bool DeleteUser(DataRow drDataRow)
199 {
200 string strSQL = string.Format("delete from users where UserID=‘{0}‘", Convert.ToInt32(drDataRow["UserID"].ToString()));
201 return ExecuteSQL(strSQL);
202 }
203
204 /// <summary>
205 /// 数据库修改
206 /// </summary>
207 /// <param name="drDataRow"></param>
208 /// <returns></returns>
209 private bool UpdateUser(DataRow drDataRow)
210 {
211 string strSQL = string.Format("update users set UserName=‘{0}‘,Password=‘{1}‘,Sex=‘{2}‘,Birthday=‘{3}‘ where UserID=‘{4}‘",
212 drDataRow["UserName"].ToString(), drDataRow["Password"].ToString(), drDataRow["Sex"].ToString(),
213 drDataRow["Birthday"].ToString(), Convert.ToInt32(drDataRow["UserID"].ToString()));
214 return ExecuteSQL(strSQL);
215 }
216
217 /// <summary>
218 /// 数据库执行SQL语句
219 /// </summary>
220 /// <param name="strSQL"></param>
221 /// <returns></returns>
222 private bool ExecuteSQL(string strSQL)
223 {
224 bool tfResult = false;
225 SqlConnection conn = new SqlConnection(strConn);
226 SqlCommand cmd = new SqlCommand(strSQL, conn);
227 try
228 {
229 conn.Open();
230 tfResult= cmd.ExecuteNonQuery().Equals(1);
231 }
232 catch (Exception ex)
233 { }
234 finally
235 {
236 conn.Close();
237 }
238
239 return tfResult;
240 }
241
242 /// <summary>
243 /// 删除
244 /// </summary>
245 /// <param name="sender"></param>
246 /// <param name="e"></param>
247 private void btn_Del_Click(object sender, EventArgs e)
248 {
249 if (this.dgv_Demo.SelectedRows.Count <= 0)
250 {
251 MessageBox.Show("请先选择要删除的行");
252 }
253 else
254 {
255 foreach(DataGridViewRow dr in this.dgv_Demo.SelectedRows)
256 {
257 //只是删除DataGridView中显示的数据，并没有删除数据库中的数据
258 this.dgv_Demo.Rows.Remove(dr);
259 }
260
261 }
262 }
263
264 /// <summary>
265 /// 增加空行
266 /// </summary>
267 /// <param name="sender"></param>
268 /// <param name="e"></param>
269 private void btn_Add_Click(object sender, EventArgs e)
270 {
271 //DataGridView没有绑定数据时才可以使用Add()方法增加空行
272 this.dgv_Demo.Rows.Add();
273 }
274
275 private void FrmMain_Load(object sender, EventArgs e)
276 {
277 this.dgv_Demo.AllowUserToAddRows = false;
278 }
279 }
280 }
时间： 2024-10-12 09:10:58