TdxBackendParameterDataType Enum

Enumerates supported value types for report/dashboard parameters.

Declaration

TdxBackendParameterDataType = (
    rptString,
    rptDateTime,
    rptDateOnly,
    rptTimeOnly,
    rptInt16,
    rptInt32,
    rptInt64,
    rptSingle,
    rptDouble,
    rptDecimal,
    rptBoolean,
    rptGuid
);

Members

Name	Description
rptString	A string value.
rptDateTime	A date/time value that stores both date and time parts.
rptDateOnly	A date/time value that stores only a date (without time part).
rptTimeOnly	A date/time value that stores only time (without a date).
rptInt16	A 16-bit signed integer value.
rptInt32	A 32-bit signed integer value.
rptInt64	A 64-bit signed integer value.
rptSingle	A single-precision floating point value (32-bit).
rptDouble	A double-precision floating point value (64-bit).
rptDecimal	A decimal numeric value.
rptBoolean	A Boolean value.
rptGuid	A Globally Unique Identifier (GUID) value (128-bit).

Remarks

TdxBackendParameterDataType values define Variant value interpretation for report/dashboard parameters.

Direct TdxBackendParameterDataType Reference

The TdxBackendCustomParameter.DataType property references a TdxBackendParameterDataType value.

Code Examples

The following code snippets use the DataType property to ensure that the expected String type is defined for the orderID parameter and assigns a string value to it.

Note

The DataType property is common to report and dashboard parameters. These examples perform the same type check and value assignment but use component-specific APIs.

Check Report Parameter Type

Delphi

uses
  dxReport.Control,       // Declares the TdxReportControl class
  dxReport.Parameters,    // Declares the TdxReportParameter class
  dxBackend.Parameters;   // Declares the TdxBackendParameterDataType enum
  System.SysUtils;        // Declares exception classes

procedure TOrderReportForm.InitReport(const AOrderID: string);
var
  AParameter: TdxReportParameter;
begin
  // Find the report parameter with the specified name
  AParameter := dxReportControl1.Parameters.FindParam('orderID');
  // Check if the parameter exists and has the String type
  if (AParameter = nil) or (AParameter.DataType <> TdxBackendParameterDataType.rptString) then
    raise Exception.Create('Missing the required parameter "orderID" of type "String".');
  AParameter.Value := AOrderID;
end;

C++

#include "dxReport.Control.hpp"       // Declares the TdxReportControl class
#include "dxReport.Parameters.hpp"    // Declares the TdxReportParameter class
#include "dxBackend.Parameters.hpp"   // Declares the TdxBackendParameterDataType enum
#include <System.SysUtils.hpp>        // Declares exception classes

// Add the following linker directives to the corresponding CPP source file:
#pragma link "dxReport.Control"   // Required to use dxReport.Control.hpp declarations

void __fastcall TOrderReportForm::InitReport(const UnicodeString &AOrderID) {
  // Find the report parameter with the specified name
  TdxReportParameter* AParameter = dxReportControl1->Parameters->FindParam(L"orderID");
  // Check if the parameter exists and has the String type
  if ((AParameter == nullptr) || (AParameter->DataType != TdxBackendParameterDataType::rptString))
    throw Exception(L"Missing the required parameter \"orderID\" of type \"String\".");
  AParameter->Value = AOrderID;
}

Check Dashboard Parameter Type

Delphi

uses
  dxDashboard.Control,      // Declares the TdxDashboardControl class
  dxDashboard.Parameters,   // Declares the TdxDashboardParameter class
  dxBackend.Parameters;     // Declares the TdxBackendParameterDataType enum
  System.SysUtils;        // Declares exception classes

procedure TDashboardForm.InitDashboard(const AOrderID: string);
var
  AParameter: TdxDashboardParameter;
begin
  // Find the dashboard parameter with the specified name
  AParameter := dxDashboardControl1.Parameters.FindParam('orderID');
  // Check if the parameter exists and has the String type
  if (AParameter = nil) or (AParameter.DataType <> TdxBackendParameterDataType.rptString) then
    raise Exception.Create('Missing the required parameter "orderID" of type "String".');
  AParameter.Value := AOrderID;
end;

C++

#include "dxDashboard.Control.hpp"      // Declares the TdxDashboardControl class
#include "dxDashboard.Parameters.hpp"   // Declares the TdxDashboardParameter class
#include "dxBackend.Parameters.hpp"     // Declares the TdxBackendParameterDataType enum
#include <System.SysUtils.hpp>        // Declares exception classes

// Add the following linker directives to the corresponding CPP source file:
#pragma link "dxDashboard.Control"   // Required to use dxDashboard.Control.hpp declarations

void __fastcall TDashboardForm::InitDashboard(const UnicodeString &AOrderID) {
  // Find the dashboard parameter with the specified name
  TdxDashboardParameter* AParameter = dxDashboardControl1->Parameters->FindParam(L"orderID");
  // Check if the parameter exists and has the String type
  if ((AParameter == nullptr) || (AParameter->DataType != TdxBackendParameterDataType::rptString))
    throw Exception(L"Missing the required parameter \"orderID\" of type \"String\".");
  AParameter->Value = AOrderID;
}