How to make a generic class, and list

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I have a database with over 60 tables where I created a corresponding class that encapsulates a property for each column in the table. I want the classes to move data between UI & the database. I want to create a generic set of code to create an instance, create a list, and add class objects with the data. The following is 2 completely manual code sets that do this for 2 sized down "user" and "project" tables:

C#

string myName = "NNNNN";
string myPassword = "PPPPP";
DBUser dbUser = new DBUser();
List<dbuser> list1 = new List<dbuser>();
list1.Add(new DBUser { Name = myName, Password = myPassword });

string myDescLong = "LLLLL";
string myDescShort = "SSSSSS";
DBProject dbProject = new DBProject();
List<dbproject> list2 = new List<dbproject>();
list2.Add(new DBProject { Desc_long = myDescLong, Descr_short = myDescShort }); 


class DBProject
{
   private string desc_long;
   public string Desc_long
   {get { return this.desc_long; } set { this.desc_long = value; }}

   private string descr_short;
   public string Descr_short
   {get { return this.descr_short; } set { this.descr_short = value; } }
}

class DBUser
{
   private string password;
   public string Password
   {get { return this.password; } set { this.password = value; }
}
   private string name;
   public string Name
   {get { return this.name; } set { this.name = value; } }
}

Now to my question. How do I generalize this so I don;t have 58 additional sets of the instance, list, add to list code? Maybe it isn't possible?

Something like send the "DbUser" classname and it can dynamically create the code below?

C#

type DBGeneric = DBUser;
type Data = "All property data";

DBGeneric dbGeneric = new DBGeneric();
List<dbgeneric> listGeneric = new List<dbgeneric>();
listGeneric.Add(new DBGeneric { Data });

Posted 4-Sep-14 21:14pm

CosmosNebula

Updated 4-Sep-14 21:43pm

George Jonsson

v3

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George Jonsson · Accepted Answer · 2014-09-04T21:43:00

You can use this code as an example of how to create a dynamic generic data type:

C#

public object CreateGeneric(Type generic, Type innerType, params object[] args)
{
    Type specificType = generic.MakeGenericType(new Type[] { innerType });
    return Activator.CreateInstance(specificType, args);
}

Then call the method with the wanted data type.
In this case I created a list with int.

C#

List<int> list = (List<int>)CreateGeneric(typeof(List<>), typeof(int));
list.Add(2);
list.Add(3);

If you are not too stuck on your own classes, you can look into the class DataTable.
Together with the class DataAdapter it is very easy to extract data form a database and show in a data grid.
This is the more generic approach and will probably save you some work.
DataAdapter Class[^]