add support for Dynamic Entity Registration in DbContext by Provides IXEntityRegisterar interface and XBaseEntityRegisterar as an abstract Implementation ...

all other requirements handled inside Module.

README.md

@@ -94,8 +94,18 @@ public class XSaherElmDbContext : XDbContext {
 
     public XSaherElmDbContext(
         DbContextOptions options,
-        XDataServiceConfiguration config
-    ) : base(options, config) { }
+        XDataServiceConfiguration config,
+        XEntityRegisterarHandlerService dynamicEntityHandlers
+    ) : base(
+        // Database nae in Data Service Configurations ...
+        "xApiDb",
+        options,
+        config,
+        dynamicEntityHandlers,
+        // a List allowed Dynamic Entity Registerars in this Context ...
+        new string[] { nameof(XStringEntityRegisterar) }
+    )
+    { }
 
     //
     public override void OnXModelCreating(ModelBuilder modelBuilder)
@@ -107,6 +117,70 @@ public class XSaherElmDbContext : XDbContext {
 }
 ```
 
+#### Dynamic Entities
+
+**xDataService** provides a solution for Dynamic Entity Registration in it's Contexts out of box.
+this is useful when some modules needs to presist data.
+
+**IXEntityRegisterar**: an interface for Describe how to Provides Dynamic Entities.
+**XBaseEntityRegisterar**: ab abstract of Implementing Dynamic Entity Providers.
+
+```C#
+public interface IXEntityRegisterar
+{}
+
+public abstract class XBaseEntityRegisterar : IXEntityRegisterar
+{}
+```
+
+for exampe we have **xStringService** which it is a module for Provides String resources in an Application. this module required to has Data Persist using Specified Entities in Implemented Application Contexts.
+
+```C#
+public class XString : XBaseIntIDEntity
+{
+    [Required]
+    [StringLength (10)]
+    public string Language { get; set; }
+
+    [Required]
+    [StringLength (255)]
+    public string ResourceTitle { get; set; }
+
+    [Required]
+    public string TranslatedValue { get; set; }        
+}
+
+public class XStringEntityConfiguration : XBaseEntityTypeConfiguration<XString, int>
+{
+    public override void Configure(EntityTypeBuilder<XString> builder)
+    {
+        builder.ToTable("Strings");
+    }
+}
+
+public class XStringEntityRegisterar : XBaseEntityRegisterar, IXEntityRegisterar
+{
+    public XStringEntityRegisterar()
+    : base(nameof(XStringEntityRegisterar))
+    {
+        //
+        // Add XString Entity ...
+        AddEntity<XString, int>();
+    }
+
+    /// <summary>
+    /// Configure Entities ...
+    /// </summary>
+    /// <param name="modelBuilder"></param>
+    public override void ConfigureEntities(ModelBuilder modelBuilder)
+    {
+        base.ConfigureEntities(modelBuilder);
+    }
+}
+```
+
+by this mechanism, provided Entity Dynamically Registered on Application DbContext automatically.
+
 #### Repository Pattern
 
 by this feature you can manipulate specified Entity using Repository Pttern implementation.