1.主体思路
- 增加学生信息：
首先将数据库中的数据填充到表（为完成能够再改的时候在dataGridView1中实时表示），然后使用sql代码(insert into 表(属性1，属性2....)values(值1，值2,.......)）进行添加。
- 删除学生信息：
使用sql代码（Delete from 表 where 条件）删除指定信息。
- 更改学生信息：
首先利用二维数组将textBox中的Text与laber进行匹配（一.是为了判断哪些没写哪些写了，二.是为了跟好的准确锁定）然后利用sql代码（update 表 set 属性=值，..... where 条件 ），这里需要注意 字符串需要加双引号（在第一个双引号的里面） 而数字（哪怕是字符串类型数字）不需要加双引号。
- 查找学生信息
使用sql代码读取所有数据库中的数据，利用OleDbDateReader read.HasRows判断是否有行，然后依次将属性列全部填充到表，再然后利用read.Read()来定位到每一行将每一行的信息都填充到表。然后for循环依次判断是否是我要找的。
操作：
1. 用C#与数据库交互，添加，删除，更改，查找。
（1 删除
OleDbConnection oleDb = new OleDbConnection(@"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=D:\access\StudentManage.mdb");//连接代码
OleDbCommand com = oleDb.CreateCommand();
oleDb.Open();
if(tag != null)
{
com.CommandText = "Delete from student where 学生编号 = " + tag;//tag是存放编号的变量
com.ExecuteReader();//运行sql命令
com.Dispose();//释放
oleDb.Close();//关闭
MessageBox.Show("删除成功！", "提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
data.Clear();
this.dataGridView1.DataSource = data;
}
else
{
MessageBox.Show("删除失败！", "提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
}
（2 添加
int count = 0;
OleDbConnection oleDb = new OleDbConnection(@"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=D:\access\StudentManage.mdb");
OleDbCommand com = oleDb.CreateCommand();
oleDb.Open();
com.CommandText = "Select * from student";
OleDbDataReader read = com.ExecuteReader();
while (read.Read())
{
count = (int)read[0];
}
count++;
com.Dispose();
oleDb.Close();
oleDb.Open();
OleDbCommand com1 = oleDb.CreateCommand();
com1.CommandText = "insert into student(学生编号,姓名,性别,年龄,语文,数学,英语,计算机网络,电话号码,身份证号)values('" + count + "','" + this.textBox1.Text +"','" + this.comboBox1.Text +"','"+ (this.textBox2.Text) + "','"+( this.textBox7.Text) +"','"+ ( this.textBox3.Text) +"','"+ ( this.textBox8.Text) +"','"+ ( this.textBox4.Text )+"','"+ this.textBox9.Text +"','"+ this.textBox5.Text +"')";
com1.ExecuteReader();
MessageBox.Show("添加成功", "提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
（3 更改
//更改
DataColumn column;
DataRow row1;
private void button2_Click(object sender, EventArgs e)
{
int[] value = new int[10];
int p = 0;
//属性与值匹配
string[,] tag = new string[2, 9]
{
{ this.textBox1.Text,
this.comboBox2.Text,
this.textBox4.Text,
this.textBox5.Text,
this.textBox6.Text,
this.textBox7.Text,
this.textBox8.Text,
this.textBox9.Text,
this.textBox3.Text
},
{
this.label2.Text,
this.label4.Text,
this.label5.Text,
this.label6.Text,
this.label7.Text,
this.label8.Text,
this.label9.Text,
this.label10.Text,
this.label3.Text
}
};
//更改： update 表 set 属性 = 值 where(可加也可不加) 条件
for (int i = 0; i < 9;i++)
{
if(tag[0,i] != "")
{
//存放值
value[p++] = i;
}
}
if(p != 0)
{
for (int i = 0; i < data.Rows.Count; i++)//遍历表
{
for (int j = 0; j < 9; j++)//遍历属性
{
column = data.Columns[j];
for (int k = 0; k < p; k++)//遍历有更改的属性
{
if (column.ColumnName == tag[1, value[k]])//判断是否相等，并更改
{
DataRow row = data.Rows[i];
row[j] = tag[0, value[k]];
}
}
}
}
this.dataGridView1.DataSource = data;
using (OleDbConnection OleDb = new OleDbConnection(@"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=D:\access\StudentManage.mdb"))
{
OleDbCommand com = OleDb.CreateCommand();
OleDb.Open();
for (int j = 0; j < data.Rows.Count; j++)
{
for (int i = 0; i < p; i++)//遍历有多少要改的属性
{
row1 = data.Rows[j];
string str1 = tag[1, value[i]];
string str2 = tag[0, value[i]];
com.CommandText = "update student set " + str1 + "=" + "'" + str2 + "'" + " where 学生编号=" + row1[0];
com.Connection = OleDb;
OleDbDataReader read = com.ExecuteReader();
read.Close();
com.Dispose();
}
}
MessageBox.Show("修改成功！", "提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
}
}
else
{
MessageBox.Show("请输入修改的值！", "警告", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
（4 查找
Button button = sender as Button;
OleDbConnection oled = new OleDbConnection(@"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=D:\access\StudentManage.mdb");
OleDbCommand com = oled.CreateCommand();
oled.Open();
com.CommandText = "Select * from student";
OleDbDataReader read = com.ExecuteReader();
DataTable data = new DataTable();
if(read.HasRows)
{
for(int i = 0; i < read.FieldCount;i++)
{
data.Columns.Add(read.GetName(i));
}
}
switch (button.Text)//依次判断有没有填
{
case "姓名":
{
while (read.Read())
{
if(read[1].ToString() == this.textBox1.Text)
{
DataRow row = data.NewRow();
for(int i = 0;i < read.FieldCount;i++)
{
row[i] = read[i];
}
data.Rows.Add(row);
}
}
this.dataGridView1.DataSource = data;
break;
}
case "年龄":
{
while (read.Read())
{
if (read[3].ToString() == this.textBox2.Text)
{
DataRow row = data.NewRow();
for (int i = 0; i < read.FieldCount; i++)
{
row[i] = read[i];
}
data.Rows.Add(row);
}
}
this.dataGridView1.DataSource = data;
break;
}
case "性别":
{
while (read.Read())
{
if (read[2].ToString() == this.comboBox1.Text)
{
DataRow row = data.NewRow();
for (int i = 0; i < read.FieldCount; i++)
{
row[i] = read[i];
}
data.Rows.Add(row);
}
}
this.dataGridView1.DataSource = data;
break;
}
case "电话号码":
{
while (read.Read())
{
if (read[8].ToString() == this.textBox3.Text)
{
DataRow row = data.NewRow();
for (int i = 0; i < read.FieldCount; i++)
{
row[i] = read[i];
}
data.Rows.Add(row);
}
}
this.dataGridView1.DataSource = data;
break;
}
case "身份证号":
{
while (read.Read())
{
if (read[9].ToString() == this.textBox4.Text)
{
DataRow row = data.NewRow();
for (int i = 0; i < read.FieldCount; i++)
{
row[i] = read[i];
}
data.Rows.Add(row);
}
}
this.dataGridView1.DataSource = data;
break;
}
}
com.Dispose();
oled.Close();
}
2.所遇问题
为了将MessBox信息窗口定时消失（遇到的问题且想了很久）
[DllImport("user32.dll", EntryPoint = "FindWindow", CharSet = CharSet.Auto)]
private extern static IntPtr FindWindow(string Lp, string Ip);
[DllImport("user32.dll", CharSet = CharSet.Auto)]
public static extern int PostMessage(IntPtr hw, int msg, IntPtr wp, IntPtr ip);
public const int WM_CLOSE = 0x10;
//后面的代码需要先调用start 然后起连锁反应
private void start()
{
Timer time = new Timer();
time.Interval = 1000;
time.Tick += new EventHandler(Timer_Tick);//时间到了之后触发
time.Start();//开始计时
}
private void Timer_Tick(object sender, EventArgs e)
{
KillMessageBox();//时间到时将其删去
((Timer)sender).Stop();//停止计时
}
private void KillMessageBox()
{
IntPtr ptr = FindWindow(null, "提示");//找到窗口句柄
if(ptr != IntPtr.Zero)
{
PostMessage(ptr, WM_CLOSE, IntPtr.Zero, IntPtr.Zero);//删除
}
}惟愿如初