1 using System;
2 using System.Collections.Generic;
3 using System.Linq;
4 using System.Text;
5 using System.Threading.Tasks;
6 using System.Data.SqlClient;
7
8 namespace 作业操作数据库
9 {
10 class Program
11 {
12 static void Main(string[] args)
13 {
14 //作业：
15 //1、让用户输入一个代号，查到一条数据（car,info），并显示
16 //2、输出提示，输入1删除该数据，输入2修改数据，输入3添加数据
17 //3、当用户输入1，把查到的这条数据删除
18 //4、当用户输入2，提示输入其他值，主键不修改，输入完成，修改这项数据
19 //5、当用户输入3，提示用户输入所有的列，然后保存到数据库
20
21 string [] AR = new string[] { "code","姓名","性别","民族","生日"};
22 //用户输入代号
23 Console.WriteLine("请输入要查询的代号");
24 string code = Console.ReadLine();
25
26 //造连接对象
27 SqlConnection conn = new SqlConnection("server=.;database=mydb;user=sa;pwd=diushiDEwutong0");
28
29 //造命令对象
30 SqlCommand cmd = conn.CreateCommand();
31
32 //给命令对象SQL语句
33 cmd.CommandText = "select * from Info where code=@code";
34 //防注入
35 //该变量绑定参数
36 cmd.Parameters.Clear();
37 cmd.Parameters.AddWithValue("@code",code);
38
39 //打开连接
40 conn.Open();
41
42 SqlDataReader dr = cmd.ExecuteReader();
43
44 if (dr.HasRows)
45 {
46 while (dr.Read())
47 {
48 int i = 0;
49
50 while (i < dr.FieldCount)
51 {
52 Console.Write(AR[i] + " ");
53 i++;
54 }
55 Console.Write("
");
56 i = 0;
57 while (i < dr.FieldCount)
58 {
59 Console.Write(dr[i] + " ");
60 i++;
61 }
62 Console.Write("
");
63 }
64 }
65 else
66 {
67 Console.WriteLine("未查询到数据");
68 while (true)
69 {
70 dr.Close();
71 Console.WriteLine("请重新输入要查询的代号");
72 code = Console.ReadLine();
73
74 cmd.CommandText = "select * from Info where code=@code";
75 cmd.Parameters.Clear();
76 cmd.Parameters.AddWithValue("@code", code);
77 dr = cmd.ExecuteReader();
78 if (dr.HasRows)
79 {
80 while (dr.Read())
81 {
82 int i = 0;
83
84 while (i < dr.FieldCount)
85 {
86 Console.Write(AR[i] + " ");
87 i++;
88 }
89 Console.Write("
");
90 i = 0;
91 while (i < dr.FieldCount)
92 {
93 Console.Write(dr[i] + " ");
94 i++;
95 }
96 Console.Write("
");
97 }
98 break;
99 }
100 else
101 {
102 Console.WriteLine("未查询到数据");
103 }
104 }
105 }
106
107
108 while (true)
109 {
110 Console.WriteLine("输入1删除该数据，输入2修改数据，输入3添加数据，输入其他跳出程序");
111 string s = Console.ReadLine();
112 if (s ==" 1")
113 {
114 if (dr.HasRows)
115 {
116 Console.WriteLine("确认删除请输入：1");
117 int sc = int.Parse(Console.ReadLine());
118 if (sc == 1)
119 {
120 dr.Close();
121 cmd.CommandText = "delete from Info where code=@code";
122 cmd.Parameters.Clear();
123 cmd.Parameters.AddWithValue("@code", code);
124 cmd.ExecuteNonQuery();
125 Console.WriteLine("删除成功");
126 }
127 else
128 {
129 Console.WriteLine("取消操作");
130 }
131 }
132 }
133 else if (s == "2")//修改内容
134 {
135 while (true)
136 {
137 dr.Close();
138 Console.Write("请输入要修改的列名：");
139 string str = Console.ReadLine();
140 string gai = "";
141 switch (str)
142 {
143 case "姓名":
144 gai = "Name";
145 break;
146 case "性别":
147 gai = "Sex";
148 break;
149 case "民族":
150 gai = "Nation";
151 break;
152 case "生日":
153 gai = "Birthday";
154 break;
155 default:
156 Console.WriteLine("输入错误");
157 continue;
158
159 }
160 if (gai == "Sex")
161 {
162 Console.Write("请输入要修改的内容：");
163 bool sex = Console.ReadLine() == "男" ? true : false;
164 cmd.CommandText = "update Info set " + gai + "='" + sex + "' where Code=@code";
165 cmd.ExecuteNonQuery();
166 }
167 else if (gai == "Nation")
168 {
169 string nationcode = "n001";
170 Console.Write("请输入要修改的内容：");
171 string nation = Console.ReadLine();
172 cmd.CommandText = "select Code from Nation where Name = '" + nation + "'";
173 dr.Close();
174 dr = cmd.ExecuteReader();
175 if (dr.HasRows)
176 {
177 dr.Read();
178 nationcode = dr[0].ToString();
179 }
180 cmd.CommandText = "update Info set " + gai + "='" + nationcode + "' where Code=@code";
181 dr.Close();
182 cmd.ExecuteNonQuery();
183 }
184 else
185 {
186 Console.Write("请输入要修改的内容：");
187 string neirong = Console.ReadLine();
188 cmd.CommandText = "update Info set " + gai + "='" + neirong + "' where Code=@code";
189 cmd.ExecuteNonQuery();
190 }
191 Console.WriteLine("修改成功!");
192 Console.WriteLine("修改后的内容为：");
193
194 cmd.CommandText = "select * from Info where code=@code";
195 cmd.Parameters.Clear();
196 cmd.Parameters.AddWithValue("@code", code);
197 dr = cmd.ExecuteReader();
198 if (dr.HasRows)
199 {
200 while (dr.Read())
201 {
202 int i = 0;
203
204 while (i < dr.FieldCount)
205 {
206 Console.Write(AR[i] + " ");
207 i++;
208 }
209 Console.Write("
");
210 i = 0;
211 while (i < dr.FieldCount)
212 {
213 Console.Write(dr[i] + " ");
214 i++;
215 }
216 Console.Write("
");
217 }
218 }
219 Console.WriteLine("是否继续修改？继续修改输入1；不修改输入任意键");
220 int b = int.Parse(Console.ReadLine());
221 if (b == 1)
222 {
223 Console.WriteLine("继续修改");
224 }
225 else
226 {
227 break;
228 }
229
230 }
231
232 }
233 else if (s == "3")//添加数据
234 {
235 //让用户输入要添加的内容
236 Console.WriteLine("请输入要添加的代号：");
237 code = Console.ReadLine();
238
239 Console.WriteLine("请输入姓名：");
240 string name = Console.ReadLine();
241
242 Console.WriteLine("请输入性别：（男或女）");
243 bool sex = Console.ReadLine() == "男" ? true : false;
244
245 Console.WriteLine("请输入民族：");
246 string nation = Console.ReadLine();
247
248 Console.WriteLine("请输入生日：");
249 string birthday = Console.ReadLine();
250
251 string nationcode = "n001";
252
253 //将民族名称转为名族代号
254 cmd.CommandText = "select Code from Nation where Name = '" + nation + "'";
255 dr.Close();
256
257 dr = cmd.ExecuteReader();
258 if (dr.HasRows)
259 {
260 dr.Read();
261 nationcode = dr[0].ToString();
262 }
263 //往Info表添加数据
264 cmd.CommandText = "insert into Info values('" + code + "','" + name + "','" + sex + "','" + nationcode + "','" + birthday + "')";
265 dr.Close();
266 cmd.ExecuteNonQuery();
267 Console.WriteLine("添加成功！");
268
269 Console.WriteLine("添加的内容为：");
270 cmd.CommandText = "select * from Info where code=@code";
271 cmd.Parameters.Clear();
272 cmd.Parameters.AddWithValue("@code", code);
273 dr = cmd.ExecuteReader();
274 if (dr.HasRows)
275 {
276 while (dr.Read())
277 {
278 int i = 0;
279
280 while (i < dr.FieldCount)
281 {
282 Console.Write(AR[i] + " ");
283 i++;
284 }
285 Console.Write("
");
286 i = 0;
287 while (i < dr.FieldCount)
288 {
289 Console.Write(dr[i] + " ");
290 i++;
291 }
292 Console.Write("
");
293 }
294 }
295
296 }
297 else
298 {
299 Console.WriteLine("程序跳出");
300 break;
301 }
302 }
303 conn.Close();
304 Console.ReadLine();
305
306
307 }
308 }
309 }