Entity Framework 6+ and Entity Framework Core with Server and Instant Feedback Modes

For v19.1+

EntityServerModeSource and EntityInstantFeedbackSource automatically detect the Entity Framework version and use appropriate EntityFunctions and SqlFunctions.

To register a custom query provider, use the DevExpress.Data.Linq.CriteriaToEFExpressionConverter.RegisterCustomQueryProviderType method:

C#
 void Application_Start() {    
     using(var context = new EfContext()) {
        var qEf = (IQueryable)context.BuildingObjects;
        var qDecompiled = (IQueryable)qEf.Decompile();
        DevExpress.Data.Linq.CriteriaToEFExpressionConverter.RegisterCustomQueryProviderType(qDecompiled.Provider.GetType(), qEf.Provider.GetType());
    }
}

For v14.1 - v19.1

Some breaking changes introduced in Entity Framework 6.0 caused compatibility issues with Entity Framework Server Mode collections (EntityServerModeSource, EntityInstantFeedbackSource).

Known issues

• Filtering via the Auto Filter Row against numeric columns is not supported.
• Searching via the Find Panel against numeric columns is not supported.
• Incremental searching against numeric columns is not supported.
• The following column group intervals are not supported:
  • Date
  • DateMonth
  • DateRange
  • DateYear
  • Default (for DateTime columns)
• A numeric column as display member of the look-up editor is not supported.
• The following function operators are not supported in filters and unbound columns.
  • ToStr (if the parameter is an operand property referencing a numeric column)
  • AddDays
  • AddHours
  • AddMilliSeconds
  • AddMinutes
  • AddMonths
  • AddSeconds
  • AddYears
  • DateDiffDay
  • DateDiffHour
  • DateDiffMilliSecond
  • DateDiffMinute
  • DateDiffMonth
  • DateDiffSecond
  • DateDiffYear
  • GetDate
• The Like operation is not supported.

Workaround

We introduced a new feature that allows you to specify classes which will be used by our library to get methods that call functions in the database.

In Entity Framework 6.0 these classes are:
System.Data.Entity.Core.Objects.EntityFunctions
System.Data.Entity.SqlServer.SqlFunctions

C#
DevExpress.Data.Linq.CriteriaToEFExpressionConverter.EntityFunctionsType = typeof(System.Data.Entity.Core.Objects.EntityFunctions);  
DevExpress.Data.Linq.CriteriaToEFExpressionConverter.SqlFunctionsType = typeof(System.Data.Entity.SqlServer.SqlFunctions);  

In Entity Framework 6.1+ the System.Data.Entity.Core.Objects.EntityFunctions is obsolete, and the System.Data.Entity.DbFunctions class should be used.

C#
DevExpress.Data.Linq.CriteriaToEFExpressionConverter.EntityFunctionsType = typeof(System.Data.Entity.DbFunctions);  
DevExpress.Data.Linq.CriteriaToEFExpressionConverter.SqlFunctionsType = typeof(System.Data.Entity.SqlServer.SqlFunctions);  

In Entity Framework Core 2.1+ only the Microsoft.EntityFrameworkCore.SqlServerDbFunctionsExtensions class should be used.

C#
DevExpress.Data.Linq.CriteriaToEFExpressionConverter.EntityFunctionsType = typeof(Microsoft.EntityFrameworkCore.SqlServerDbFunctionsExtensions);  

If you experience issues listed in the description to this article, execute the code above in your application's entry point. This will resolve problems caused by this limitation.

Note: The information above is applicable only for Server Mode data sources, because they configure the CriteriaToEFExpressionConverter instance internally. If you are creating the CriteriaToEFExpressionConverter instance manually (e.g., for the CriteriaToQueryableExtender.AppendWhere method), you also need to pass the query type to its constructor:

C#
var result = CriteriaToQueryableExtender.AppendWhere(queryable, new CriteriaToEFExpressionConverter(queryable.Provider.GetType()), criteria);