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using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Data.SqlClient;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace 省市选择
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
using (SqlConnection coon = new SqlConnection(@"Data Source=(LocalDB)\v11.0;AttachDbFilename=E:\新建文件夹\exam\test9\SQLtest9.mdf;Integrated Security=True"))
{
cmbshi.Items.Clear();
coon.Open();
using(SqlCommand cmd=coon.CreateCommand())
{
cmd.CommandText = "select * from shen;";
using(SqlDataReader reader=cmd.ExecuteReader())
{
while (reader.Read())
{
ids id = new ids();
id.id= reader.GetInt32(reader.GetOrdinal("id"));
id.shen=reader.GetString(reader.GetOrdinal("省"));
cmbshen.Items.Add(id);
}
}
}
}
}
private void cmbshen_SelectedIndexChanged(object sender, EventArgs e)
{
txtqh.Clear();
ids item = (ids)cmbshen.SelectedItem;
int id1 = item.id;
using (SqlConnection coon = new SqlConnection(@"Data Source=(LocalDB)\v11.0;AttachDbFilename=E:\新建文件夹\exam\test9\SQLtest9.mdf;Integrated Security=True"))
{
coon.Open();
using (SqlCommand cmd = coon.CreateCommand())
{
cmd.CommandText = "select * from city where id=@id";
cmd.Parameters.Add(new SqlParameter("@id", id1));
using (SqlDataReader reader = cmd.ExecuteReader())
{
while (reader.Read())
{
ids shi=new ids();
cmbshi.Items.Add(reader.GetString(reader.GetOrdinal("市")));
}
}
}
}
}
private void cmbshi_SelectedIndexChanged(object sender, EventArgs e)
{
string shi = (string)cmbshi.SelectedItem;
using (SqlConnection coon = new SqlConnection(@"Data Source=(LocalDB)\v11.0;AttachDbFilename=E:\新建文件夹\exam\test9\SQLtest9.mdf;Integrated Security=True"))
{
coon.Open();
using (SqlCommand cmd = coon.CreateCommand())
{
cmd.CommandText = "select * from city where 市=@id";
cmd.Parameters.Add(new SqlParameter("@id", shi));
using (SqlDataReader reader = cmd.ExecuteReader())
{
while (reader.Read())
{
txtqh.Text=reader.GetString(reader.GetOrdinal("quhao"));
}
}
}
}
}
}
class ids
{
public int id{get;set;}
public string shen { get; set; }
}
}