这是别的地方实例化子类构造方法传值(加断点,在这con是有值的)
public ServiceStationData dataAccess = new ServiceStationData(con);子类:
public partial class ServiceStationData : BaseData
{
public ServiceStationData(string con)
{ BaseData.con = con; }
}
父类:
public class BaseData : RootSqlData
{ public static string con;
internal BasicDataAccess basicDataAccess = new BasicDataAccess(con);
}
加断点到了子类和父类里con都是是null
你可以用父类类名.静态变量 = 值来赋值。但是只有子类被调用,才会改变,为此,你可以用虚函数:public static string con;
=>
private static string con;
public static void SetCon(string constr)
{
con = constr;
basicDataAccess = new BasicDataAccess(con);
}
子类:
public partial class ServiceStationData : BaseData
{
public ServiceStationData(string con)
{
BaseData.SetCon(con);
}
}
在调用子类的构造,所以你的basicDataAccess里的con是空