namespace 省市选择
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
} private void cmd省_SelectedIndexChanged(object sender, EventArgs e)
{ } private void Form1_Load(object sender, EventArgs e)
{
using (SqlConnection = new SqlConnection(@"Data Source=.\SQLEXPRESS:ArrachDbFilename=|DataDirectory|\ss.mdf;Inegrated Security=true;user Instance=true"))
{
conn.Opne();
using (SqlCommand cmd=conn. CreateCommand())
{
cmd.CommandText="slecet * from promary";
using(SqlDataReader dataReader= cmd.ExecuteReader())
{
while(dataReader .Read ())
{
provinceItem item = new provinceItem();
item.Id = dataReader.GetInt32(dataReader .GetOrdinal ("proID"));
item.Name = dataReader.GetInt32(dataReader.GetOrdinal(proName));
cmd省.Items.Add(item);
}
} }
}
} private void cmd省_SelectionChangeCommitted(object sender, EventArgs e)
{
provinceItem item=(provinceItem )cmd省 .SelectedItem;
int proID=item.Id ; using (SqlConnection conn = new SqlConnection(@"Data Source=.\SQLEXPRESS:ArrachDbFilename=|DataDirectory|\ss.mdf;Inegrated Security=true;user Instance=true"))
{
conn.Opne();
using (SqlCommand cmd=conn. CreateCommand())
{
cmd.CommandText="slecet * from city where proID=@proID";
cmd.Parameters .Add (new SqlParameter ("proID",proID));
using(SqlDataReader dataReader= cmd.ExecuteReader())
{
while(dataReader .Read ())
{ string cityName=dataReader .GetString (dataReader .GetOrdinal ("cityName"));
cmd市 .Items.Add (cityName);
}
} }
}
}
}
class provinceItem
{
public string Name{ get; set;}
public int Id { get; set;}
}
}运行是会报错:,不知道那位高手能帮我解决一下这个问题
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
} private void cmd省_SelectedIndexChanged(object sender, EventArgs e)
{ } private void Form1_Load(object sender, EventArgs e)
{
using (SqlConnection = new SqlConnection(@"Data Source=.\SQLEXPRESS:ArrachDbFilename=|DataDirectory|\ss.mdf;Inegrated Security=true;user Instance=true"))
{
conn.Opne();
using (SqlCommand cmd=conn. CreateCommand())
{
cmd.CommandText="slecet * from promary";
using(SqlDataReader dataReader= cmd.ExecuteReader())
{
while(dataReader .Read ())
{
provinceItem item = new provinceItem();
item.Id = dataReader.GetInt32(dataReader .GetOrdinal ("proID"));
item.Name = dataReader.GetInt32(dataReader.GetOrdinal(proName));
cmd省.Items.Add(item);
}
} }
}
} private void cmd省_SelectionChangeCommitted(object sender, EventArgs e)
{
provinceItem item=(provinceItem )cmd省 .SelectedItem;
int proID=item.Id ; using (SqlConnection conn = new SqlConnection(@"Data Source=.\SQLEXPRESS:ArrachDbFilename=|DataDirectory|\ss.mdf;Inegrated Security=true;user Instance=true"))
{
conn.Opne();
using (SqlCommand cmd=conn. CreateCommand())
{
cmd.CommandText="slecet * from city where proID=@proID";
cmd.Parameters .Add (new SqlParameter ("proID",proID));
using(SqlDataReader dataReader= cmd.ExecuteReader())
{
while(dataReader .Read ())
{ string cityName=dataReader .GetString (dataReader .GetOrdinal ("cityName"));
cmd市 .Items.Add (cityName);
}
} }
}
}
}
class provinceItem
{
public string Name{ get; set;}
public int Id { get; set;}
}
}运行是会报错:,不知道那位高手能帮我解决一下这个问题
public int Id { get{return (int)}; set{};}
{
public string Name{ get; set;}
public int Id { get; set;}
} 在VS2005下是不行的。VS2008可以。
{
public string Name{ get; set;}
public int Id { get; set;}
} 在 C# 3.0 和更高版本中,当属性的访问器中不需要其他逻辑时,自动实现的属性可使属性声明更加简洁。
抄袭 c++/cli 引入关键字不行么?
{//省选项
private int id;
private string proName; public string Name {
get { return this.proName; }
set { this.proName = value; }
}
public int ID
{
get { return this.id ; }
set { this.id = value; }
}
这样就可以了
如果是3.0以下版本的话,你的属性访问器需要有明确的实现
get,set相当与就是属性的 获取和设值的方法名,set默认有一个参数 valueget{ return .... } 需要你返回一个值set{ ...= value;}把值付给你的变量