private void button1_Click(object sender, EventArgs e)
{
if (textBox1.Text == "" || textBox2.Text == "" || textBox3.Text == "")
{
MessageBox.Show("输入能为空", "提示");
return;
}
if (textBox3.Text != "1" && textBox3.Text != "2" && textBox3.Text != "3")
{
MessageBox.Show("权限等级只能为（1,2,3）", "提示");
return;
}
DBcon DB = new DBcon();
string str = "insert into Table_users values ('" + textBox1.Text.Trim() + "','" + textBox2.Text.Trim() + "','" + textBox3.Text.Trim() + "')";
try
{
DBcon.GetCon();
DB.ExecuteUpdate(str);
MessageBox.Show("添加成功！");
}
catch (Exception ex)
{
MessageBox.Show(ex.Message, "错误");
}
finally
{
DB.Con_Close();
}
}
private void button4_Click(object sender, EventArgs e)
{
try
{
//打开数据库并创建实例
DBcon.GetCon();
DBcon db = new DBcon();
//选中项的列名
string strcolumn = dataGridView1.Columns[this.dataGridView1.CurrentCell.ColumnIndex].HeaderText;
//选中项所在行的学号
string strrow = Convert.ToString(dataGridView1.CurrentRow.Cells[0].Value);
//选中的值
string value = dataGridView1.SelectedCells[0].Value.ToString();
//更新语句
string strcom = "update Students set " + strcolumn + "='" + value + "' where 学号 = " + strrow;
//更新操作
db.ExecuteUpdate(strcom);
MessageBox.Show("修改成功！");
}
catch (Exception ex)
{
MessageBox.Show(ex.Message, "错误");
}
finally
{
DBcon.sql_con.Close();
}
}
private void button4_Click(object sender, EventArgs e)
{
try
{
//判断是否有信息可以删除
if (dataGridView1.SelectedRows.Count == 0)
{
MessageBox.Show("未选中或无可删除信息！");
return;
}
//删除选中的行
if (MessageBox.Show("确定删除选中的行？", "提示", MessageBoxButtons.YesNo) == DialogResult.Yes)
{
string str = "delete Table_users where id = '" + dataGridView1.SelectedRows[0].Cells["id"].Value + "'";
DBcon db = new DBcon();
DBcon.GetCon();
db.ExecuteUpdate(str);
MessageBox.Show("删除成功!");
}
else
{
return;
}
}
catch (Exception ex)
{
MessageBox.Show(ex.Message, "错误");
}
}
private void button2_Click(object sender, EventArgs e)
{
DBcon con = new DBcon();
if (textBox1.Text == "" || textBox2.Text == "")
{
MessageBox.Show("请先输入要添加的信息！");
return;
}
try
{
string str = "insert into Students values ('" + textBox1.Text + "','" + textBox2.Text + "','" + textBox3.Text + "','" + textBox4.Text + "','" + textBox5.Text + "','" + textBox6.Text + "','" + textBox7.Text + "')";
DBcon.GetCon();
DBcon DB = new DBcon();
DB.ExecuteUpdate(str);
MessageBox.Show("插入成功！");
}
catch (Exception ex)
{
MessageBox.Show(ex.Message, "提示");
}
finally
{
con.Con_Close();
}
}
private void button1_Click(object sender, EventArgs e)
{
DBcon Db = new DBcon();
string str = "select * from Table_users";
DataSet ds = Db.GetDataSet(str, "Table_users");
this.dataGridView1.DataSource = ds.Tables["Table_users"].DefaultView;
}
private void button1_Click(object sender, EventArgs e)
{
string str = "select * from Students";
DBcon con = new DBcon();
DataSet ds = con.GetDataSet(str, "Students");
this.dataGridView1.DataSource = ds.Tables["Students"].DefaultView;
}
private void button6_Click(object sender, EventArgs e)
{
string str1 = comboBox1.Text.ToString();
string str2 = textBox8.Text.ToString().Trim();
if (str1 == "" || str2 == "")
{
MessageBox.Show("输入不能为空！");
return;
}
string str = "select * from Students where " + str1 + "='" + str2 + "'";
DBcon con = new DBcon();
DataSet ds = con.GetDataSet(str, "Students");
this.dataGridView1.DataSource = ds.Tables["Students"].DefaultView;
}
private void button3_Click(object sender, EventArgs e)
{
//判断是否有信息可以删除
if (dataGridView1.SelectedRows.Count == 0)
{
MessageBox.Show("没有可删除信息！");
return;
}
//删除选中的行
if (MessageBox.Show("确定删除选中的行？", "提示", MessageBoxButtons.YesNo) == DialogResult.Yes)
{
string str = "delete Students where 学号 = '" + dataGridView1.SelectedRows[0].Cells["学号"].Value + "'";
DBcon db = new DBcon();
DBcon.GetCon();
db.ExecuteUpdate(str);
MessageBox.Show("删除成功!");
}
else
{
return;
}
}