asp.net 国家,省,城市三级联动

下面代码当中,国家我设置的只是中国,当然也可以从数据里取出别的国家来.






BinderToNationOrArea()绑定国家或地区,省份或洲,城市#region BinderToNationOrArea()绑定国家或地区,省份或洲,城市






/**//// <summary>


/// 绑定国家或地区


/// </summary>


/// <param name="sender"></param>


/// <param name="e"></param>


private void BinderToNationOrArea()




...{


//打开数据库的连接


if (cn.State == System.Data.ConnectionState.Closed)


cn.Open();


//国家或地区


SqlCommand cmd = new SqlCommand("select * from NationArea where NationArea = '中国' ",cn);


SqlDataReader sdr = cmd.ExecuteReader();


this.ddlNationOrArea.DataSource = sdr;


this.ddlNationOrArea.DataTextField = "NationArea";


this.ddlNationOrArea.DataValueField = "NationAreaID";


this.ddlNationOrArea.DataBind();


sdr.Close();




//省份或洲


//得到国家的ＩＤ


string NationAreaID = this.ddlNationOrArea.SelectedValue;




cmd.CommandText = "select * from Province where NationAreaID = '" + NationAreaID + "'";


sdr = cmd.ExecuteReader();


this.ddlProvince.DataSource = sdr;


this.ddlProvince.DataTextField = "ProvinceName";


this.ddlProvince.DataValueField = "ProvinceID";


this.ddlProvince.DataBind();


sdr.Close();




//城市


//得到省的ＩＤ


string ProvinceID = this.ddlProvince.SelectedValue;


cmd.CommandText = "select * from City where ProvinceID = '" + ProvinceID + "'";


sdr = cmd.ExecuteReader();


this.ddlCity.DataSource = sdr;


this.ddlCity.DataTextField = "CityName";


this.ddlCity.DataValueField = "CityID";


this.ddlCity.DataBind();


sdr.Close();


//关闭数据库的连接


cn.Close();




//本个控件的值


//国家


this.txtNationOrArea.Text = this.ddlNationOrArea.SelectedItem.Text.Trim();


//省


this.txtProvince.Text = this.ddlProvince.SelectedItem.Text.Trim();


//市


this.txtCity.Text = this.ddlCity.SelectedItem.Text.Trim();




//显示邮政编码


this.PostCode();


}






#endregion




BinderToProvince()绑定各个省,或洲#region BinderToProvince()绑定各个省,或洲






/**//// <summary>


/// 绑定各个省,或洲


/// </summary>


/// <param name="sender"></param>


/// <param name="e"></param>


private void BinderToProvince()




...{


if (cn.State == System.Data.ConnectionState.Closed)


cn.Open();


//省份或洲


//得到国家的ＩＤ


string NationAreaID = this.ddlNationOrArea.SelectedValue;




SqlDataAdapter sda = new SqlDataAdapter("select * from Province where NationAreaID = '" + NationAreaID + "'",cn);


DataSet ds = new DataSet();


sda.Fill(ds,"Province");


this.ddlProvince.DataSource = ds.Tables["Province"];


this.ddlProvince.DataTextField = "ProvinceName";


this.ddlProvince.DataValueField = "ProvinceID";


this.ddlProvince.DataBind();




//城市


//得到省的ＩＤ


string ProvinceID = this.ddlProvince.SelectedValue;


sda.Fill(ds,"City");


this.ddlCity.DataSource =ds.Tables["City"];


this.ddlCity.DataTextField = "CityName";


this.ddlCity.DataValueField = "CityID";


this.ddlCity.DataBind();


//关闭数据库的连接


cn.Close();




//省


this.txtProvince.Text = this.ddlProvince.SelectedItem.Text.Trim();


//城市


this.txtCity.Text = this.ddlCity.SelectedItem.Text.Trim();




//显示相应邮政编码


this.PostCode();


}






#endregion




BinderToCity() 绑定各个城市#region BinderToCity() 绑定各个城市




/**//// <summary>


/// 绑定各个城市


/// </summary>


/// <param name="sender"></param>


/// <param name="e"></param>


private void BinderToCity()




...{


if (cn.State == System.Data.ConnectionState.Closed)


cn.Open();


//城市


//得到省的ＩＤ


string ProvinceID = this.ddlProvince.SelectedValue;




SqlDataAdapter sda = new SqlDataAdapter("select * from City where ProvinceID = '" + ProvinceID + "'",cn);


DataSet ds = new DataSet();


sda.Fill(ds,"City");


this.ddlCity.DataSource = ds.Tables["City"];


this.ddlCity.DataTextField = "CityName";


this.ddlCity.DataValueField = "CityID";


this.ddlCity.DataBind();


//关闭数据库的连接


cn.Close();


//省


this.txtProvince.Text = this.ddlProvince.SelectedItem.Text.Trim();


//市


this.txtCity.Text = this.ddlCity.SelectedItem.Text.Trim();




//显示相应的邮政编码


this.PostCode();


}


#endregion