TdxInputQueryValidationProc Type

The procedural type for validation routines used in input query dialogs.

Declaration

TdxInputQueryValidationProc = reference to procedure(ValueIndex: Integer; const Value: string; var IsValid: Boolean);

Parameters

Name	Type	Description
ValueIndex	Integer	The index of the currently evaluated string.
Value	string	The currently evaluated string.
IsValid	Boolean	If False, the input dialog box disables the OK button and ignores the Enter keystroke. If True, the content of all displayed text editors is considered valid.

Remarks

The following code example demonstrates a validation routine that disables the OK button and ignores the Enter keystroke if at least one of the displayed text editors is empty:

Delphi

uses
  dxInputDialogs;  // This unit declares the dxInputQuery function
// ...

procedure TMyForm.ValidationProcedure(ValueIndex: Integer; const Value: string; var IsValid: Boolean);
begin
  if Value = '' then  // Disables the "OK" button if at least one editor value is an empty string
    IsValid := False;
end;

procedure TMyForm.cxButton1Click(Sender: TObject);
var
  APrompts, AValues: array of string;
begin
  SetLength(APrompts, 2);
  SetLength(AValues, 2);
  APrompts[0] := 'First Name:';
  APrompts[1] := 'Last Name';
  dxInputQuery('New User', APrompts, AValues, ValidationProcedure);
end;

C++

#include "dxInputDialogs.hpp"  // This header declares the dxInputQuery function
// ...

void __fastcall TMyForm::ValidationProcedure(int ValueIndex, const UnicodeString Value, bool &IsValid)
{
  if(Value == "")  // Disables the "OK" button if at least one editor value is an empty string
    IsValid = false;
}

void __fastcall TMyForm::cxButton1Click(TObject *Sender)
{
  UnicodeString *APrompts = nullptr;
  UnicodeString *AValues = nullptr;

  SetLength(APrompts, 2);
  SetLength(AValues, 2);
  APrompts[0] = "First Name:";
  APrompts[1] = "Last Name:";
  dxInputQuery("New User", APrompts, 2, AValues, 2, ValidationProcedure);
}

Direct TdxInputQueryValidationProc Procedural Type References

The following global methods accept a routine of the TdxInputQueryValidationProc type as the AValidationProc parameter:

dxInputQuery(string,string,string,TdxInputQueryValidationProc)

Invokes a modal input dialog box that prompts a user to enter a string and checks if the user input is valid.

dxInputQuery(string,string[],string[],TdxInputQueryValidationProc)

Invokes an input dialog box that allows users to enter a string.

dxSelectQuery(string,string,TStrings,string,Boolean,TdxInputQueryValidationProc)

Invokes a modal input dialog box that allows users to select a value in a combo box.