Delphi – Limit the maximum text length of the Inplace editor in TDBGRID

procedure TInplaceEdit.UpdateContents;
begin
 Text :='';
 EditMask := Grid.GetEditMask(Grid.Col, Grid.Row);
 Text := Grid.GetEditText(Grid.Col, Grid.Row);
 MaxLength := Grid.GetEditLimit;< br />end;

function TCustomDBGrid.GetEditMask(ACol, ARow: Longint): string;
 begin
 Result :='';
 if FDatalink.Active then
 with Columns[RawToDataColumn(ACol)] do
 if Assigned(Field) then
 Result := Field.EditMask;
end;

function TCustomDBGrid.GetEditLimit: Integer;
begin
 Result := 0;
 if Assigned(SelectedField) and (SelectedField.DataType in [ftString, ftWideString]) then
 Result := SelectedField.Size;
end;

// Opening of dataset< br />...
DataSet.FieldByName('FloatField').EditMask := '00.00';

uses
 Data.DB,
 Vcl.DBGrids;

type
 TMyDBGrid = class(TDBGrid)
 protected
 function GetEditLimit: Integer; override;
 end;

implementation

{ TMyDBGrid }

function TMyDBGrid.GetEditLimit: Integer;
begin
 Result := inherited GetEditLimit;
 if (Result = 0) and Assigned(SelectedField) and (SelectedField.DataType = ftFloat) then
 Result := 5; // Whatever you decide
end;

How to limit the maximum text length of the inplace editor in TDBGrid? (Delphi Berlin)

The data type is Float.

The inplace editor in TDBGrid will update its content by calling< p>

procedure TInplaceEdit.UpdateContents;
begin
 Text :='';
 EditMask := Grid.GetEditMask(Grid.Col , Grid.Row);
 Text := Grid.GetEditText(Grid.Col, Grid.Row);
 MaxLength := Grid.GetEditLimit;
end;

The implementation of GetEditMask is as follows:

function TCustomDBGrid.GetEditMask(ACol, ARow: Longint): string;
begin
 Result :='';< br /> if FDatalink.Active then
 with Columns[RawToDataColumn(ACol)] do
 if Assigned(Field) then
 Result := Field.EditMask;
end; 
and GetEditLimit like this:
 
 
function TCustomDBGrid.GetEditLimit: Integer;
begin
 Result := 0;
 if Assigned(SelectedField) and (SelectedField.DataType in [ftString, ftWideString]) then
 Result := SelectedField.Size;
end;
There, you have multiple ways to Achieve the behavior I want.
>Use the TField EditMask attribute for the field to be restricted. This will be returned by the Grid.GetEditMask call. No need from TDBGrid inherits and overrides anything. You can control the behavior on a field-by-field basis.
>Create your own TDBGrid descendants and override GetEditLimit
Return MaxLength for the inplace editor based on SelectedField
Method 1 The code might look like this:

// Opening of dataset
...
DataSet.FieldByName('FloatField').EditMask := '00.00 ';
This will mask the need for two digits before and after the decimal separator. For more information about the mask, see TEditMask
Method 2 :

uses
 Data.DB,
 Vcl.DBGrids;

type
 TMyDBGrid = class(TDBGrid )
 protected
 function GetEditLimit: Integer; override;
 end;

implementation

{ TMyDBGrid }

function TMyDBGrid.GetEditLimit: Integer;
begin
 Result := inherited GetEditLimit;
 if (Result = 0) and Assigned(SelectedField) and (SelectedField.DataType = ftFloat) then
 Result := 5; // Whatever you decide
end;
As kobik suggested, you can use this class as an insert class. For this, add TDBGrid = class(TMyDBGrid ); in the cell where you want to use the grid. If you declare TMyDBGrid in the same cell where you want to use it, please make the type reference clear TMyDBGrid = class(Vcl.DBGrids.TDBGrid).