ICustomFunctionOperatorFormattable Interface

Defines server-side processing for custom functions.

Namespace: DevExpress.Data.Filtering

Assembly: DevExpress.Data.v18.1.dll

Declaration

C#

public interface ICustomFunctionOperatorFormattable :
    ICustomFunctionOperator

VB.NET

Public Interface ICustomFunctionOperatorFormattable
    Inherits ICustomFunctionOperator

Related API Members

The following members accept/return ICustomFunctionOperatorFormattable objects:

• ConnectionProviderSql.GetCustomFunctionOperator(String)

Remarks

Implement this interface in addition to the ICustomFunctionOperator interface to provide a database-specific SQL command for your custom function. This interface declares the functionality required to evaluate the custom function within criteria on the database server.

If you want to make your custom function available to end-users in Expression Editors, implement the ICustomFunctionOperatorBrowsable interface as well.

Related GitHub Examples

The following code snippets (auto-collected from DevExpress Examples) contain references to the ICustomFunctionOperatorFormattable interface.

Note

The algorithm used to collect these code examples remains a work in progress. Accordingly, the links and snippets below may produce inaccurate results. If you encounter an issue with code examples below, please use the feedback form on this page to report the issue.

C#

XPO_how-to-implement-the-icustomfunctionoperatorformattable-interface-e2491/CS/DatePartFunction.cs#L8

namespace DXSample {
    public class GetMonthFunction :ICustomFunctionOperatorFormattable, ICustomFunctionOperatorQueryable {
        #region ICustomFunctionOperatorFormattable Members

server-mode-how-to-implement-a-distinct-count-aggregation-function-t329175/CS/CustomFunction_DistinctCount/DistinctCountFunction.cs#L11

namespace XPG_ServerMode_EF {
    class DistinctCountFunction : ICustomFunctionOperator, ICustomFunctionOperatorFormattable, IQueryableConvertible {
        internal const string Name = "DistinctCount";

Reporting_how-to-use-a-custom-function-in-a-query-expression-t352441/CS/SelectQueryWindowsFormsApplication/StDevOperator.cs#L7

namespace SelectQueryWindowsFormsApplication {
    public sealed class StDevOperator : ICustomFunctionOperatorBrowsable, ICustomFunctionOperatorFormattable {
        const string name = "StDev";

VB.NET

XPO_how-to-implement-the-icustomfunctionoperatorformattable-interface-e2491/VB/DatePartFunction.vb#L10

Public Class GetMonthFunction
    Implements ICustomFunctionOperatorFormattable, ICustomFunctionOperatorQueryable
    #Region "ICustomFunctionOperatorFormattable Members"

server-mode-how-to-implement-a-distinct-count-aggregation-function-t329175/VB/CustomFunction_DistinctCount/DistinctCountFunction.vb#L12

Friend Class DistinctCountFunction
    Implements ICustomFunctionOperator, ICustomFunctionOperatorFormattable, IQueryableConvertible

Reporting_how-to-use-a-custom-function-in-a-query-expression-t352441/VB/SelectQueryWindowsFormsApplication/StDevOperator.vb#L8

Public NotInheritable Class StDevOperator
    Implements ICustomFunctionOperatorBrowsable, ICustomFunctionOperatorFormattable