//改
public void updateData(MySqlData data)
{
if (this.OpenConection() == true)
{
string text = "update nanning_city set area_name='"
+ data.Area + "',name='" + data.Name + "',price="
+ data.Price + " where id=" + data.Id + ";";
string text1 = "select count(*) from nanning_city where area_name = '"
+ data.Area + "' and name='" + data.Name + "' and price="
+ data.Price + ";";
if (this.OpenConection())
{
this.cmd = new MySqlCommand(text1, con);
int count = Convert.ToInt32(cmd.ExecuteScalar());
if (count > 0)
{
MessageBox.Show("数据已存在！");
}
else
{
cmd = new MySqlCommand(text, con);
cmd.ExecuteNonQuery();
this.CloseConnection();
MessageBox.Show("修改成功！");
}
}
}
this.CloseConnection();
}
//增
public void addData(MySqlData data)
{
string text = "insert into nanning_city" +
"(area_name,name,price) values('" +
data.Area + "','" + data.Name + "','" + data.Price + "');";
string text1 = "select count(*) from nanning_city where area_name = '"
+ data.Area + "' and name='" + data.Name + "' and price="
+ data.Price + ";";
if (this.OpenConection() == true)
{
//查询插入数据是否已经存在
this.cmd = new MySqlCommand(text1, con);
int count = Convert.ToInt32(cmd.ExecuteScalar());
if (count > 0)
{
MessageBox.Show("数据已存在！");
}
else
{
this.cmd = new MySqlCommand(text, con);
this.cmd.ExecuteNonQuery();
this.CloseConnection();
MessageBox.Show("数据添加成功！");
}
}
}
public ModificationForm(MySqlData data)
{
InitializeComponent();
textBox4.Text = data.Area;
textBox5.Text = data.Name;
textBox6.Text = data.Price.ToString();
this.selected = data.Id;
}
private void button1_Click(object sender, EventArgs e)
{
try
{
MySqlData data = new MySqlData();
data.Area = textBox1.Text;
data.Name = textBox2.Text;
data.Price = int.Parse(textBox3.Text);
data.Id = this.selected;
new MySqlDA().updateData(data);
}
catch
{
MessageBox.Show("Price必须为数字！请重新输入！");
}
}
private void button3_Click(object sender, EventArgs e)
{
MySqlData data = new MySqlData();
if (listView1.SelectedItems.Count > 0)
{
if (MessageBox.Show(
"请再次确定您是否要删除该数据！", "提示", MessageBoxButtons.YesNo)
== DialogResult.Yes)
{
data.Id = int.Parse(listView1.SelectedItems[0].SubItems[0].Text);
new MySqlDA().deleteData(data.Id);
refreshListView();
}
}
else
{
MessageBox.Show("请在表格中选择要删除的数据！");
}
}
private void button4_Click(object sender, EventArgs e)
{
MySqlData data = new MySqlData();
if (listView1.SelectedItems.Count > 0)
{
//获得选中的数据
data.Id = int.Parse(listView1.SelectedItems[0].SubItems[0].Text);
data.Area = listView1.SelectedItems[0].SubItems[1].Text;
data.Name = listView1.SelectedItems[0].SubItems[2].Text;
data.Price = float.Parse(listView1.SelectedItems[0].SubItems[3].Text);
ModificationForm modification = new ModificationForm(data);
modification.form1 = this;
modification.Owner = this;
modification.Show();
}
else
{
MessageBox.Show("请先在表格中选择需要更改的数据！");
}
}
//查
public List <MySqlData> queryData(string area)
{
List <MySqlData> list = new List <MySqlData>();
string text = "select * from nanning_city where area_name like '%" + area + "%';";
if (this.OpenConection() == true)
{
this.cmd = new MySqlCommand(text, con);
MySqlDataReader mySqlDataReader = cmd.ExecuteReader();
while (mySqlDataReader.Read())
{
MySqlData data = new MySqlData();
data.Id = int.Parse(mySqlDataReader["id"].ToString());
data.Area = mySqlDataReader["area_name"].ToString();
data.Name = mySqlDataReader["name"].ToString();
data.Price = float.Parse(mySqlDataReader["price"].ToString());
list.Add(data);
}
}
this.CloseConnection();
return(list);
}
private void button1_Click(object sender, EventArgs e)
{
if (textBox1.Text != "" && textBox2.Text != "" && textBox3.Text != "")
{
try
{
MySqlData udata = new MySqlData();
udata.Area = textBox1.Text;
udata.Name = textBox2.Text;
udata.Price = int.Parse(textBox3.Text);
new MySqlDA().addData(udata);
}
catch
{
MessageBox.Show("Price必须为数字！请重新输入！");
}
}
else
{
MessageBox.Show("输入不能为空！");
}
}
