Using pluralised table names with C# generics in MVC

Question

I'm trying to create a generic function that will be used to access multiple tables in my database. Is there a way to used pluralised (pluralized for the non-British!) table names with my generic function.

I may be thinking about this the wrong way (fairly new to generics/templates), but here's my code (Db is just a global var for access to my database):

public void UpdateMyTables<TEntity>() {
    // string plural = EntityObject<TEntity>.GetTableName(); // OR SOMETHING SIMILAR??
    IEnumerable<EntityType> entitiesToUpdate = Db.<TEntity>; // Obviously doesn't work because TEntity is not a table name, it's an object type

    foreach(<TEntity> e in entitiesToUpdate) {
        e.MyColumn = "A string that I'm updating all these fields with";
    }
}

So my question is: do I need to do some hackery to get the pluralised table name, or is there a function designed to return this (like GetTableName), or should I come at this from a different angle?

I also found a link that would help with the manual conversion here: Pluralising in mvc

Hugs and kisses and thanks in advance...

I'm guessing this should be tagged #Entity-Framework? – hometoast Apr 30 '13 at 10:39 — hometoast, Apr 30 '13 at 10:39

score 2 · Accepted Answer · edited May 23 '17 at 12:04

You can use the .Set() method to get the IEnumerable:

IEnumerable<TEntity> entitiesToUpdate = Db.Set<TEntity>();

To get the Table Name you could possibly use the code from this blog post or this SO answer.

The foreach should be written:

foreach(TEntity e in entitiesToUpdate) { // you can use "var" here if you prefer
    e.MyColumn = "A string that I'm updating all these fields with";
}

Now, the problem is that TEntity does not have a .MyColumn property. If you are using this method with entities that inherit from a base class (called for example BaseEntity), which has that property, you can change the method declaration like this:

public void UpdateMyTables<TEntity>() where TEntity : BaseEntity {

This limits you to pass to call this method only with Entities that inherits from BaseEntity, but will give you access to the public properties and methods defined in BaseEntity.

To make the code above work, Base Entity should be declared like this:

public class BaseEntity { //of course it can be abstract or an interface...
    public string MyColumn { get; set; }
}

I hope I understood what you wanted to do. If you need further information let us know. :)

Hey thanks for the extensive answer (+1). Although I'm having issues with the second half - my `TEntities` inherit from: `public interface IPreparable { T Prepare(DdqEntities db); }` and I can't get rid of the *TEntity does not have a .MyColumn property* even when adding `where TEntity: IPreparable` like you say above. Any suggestions? — WheretheresaWill, Apr 30 '13 at 11:20
If the interface is what you wrote, meaning that it only has a method `Prepare(...)` then you can only call that method on your generic. I have detailed what the BaseEntity has to look like. — Tallmaris, Apr 30 '13 at 13:10
Ah okay I understand. I'll have to refactor my code a bit to get this to work. Thanks again. — WheretheresaWill, Apr 30 '13 at 13:15

Using pluralised table names with C# generics in MVC

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