Compares two strings by ordinal value without case sensitivity.
function CompareText(const S1: string; const S2: string): Integer; overload; function CompareText(const S1: string; const S2: string; LocaleOptions: TLocaleOptions): Integer; overload;
int CompareText(const AnsiString S1, const AnsiString S2); int CompareText(const AnsiString S1, const AnsiString S2, TLocaleOptions LocaleOptions);
SysUtils
CompareText compares S1 and S2 and returns 0 if they are equal. If S1 is greater than S2, CompareText returns an integer greater than 0. If S1 is less than S2, CompareText returns an integer less than 0. CompareText is not case sensitive and is not affected by the current locale.
C++ Examples:
/* The following code orders a list view in reverse alphabetical order on the click of a button. The callback function CustomSortProc calls the global CompareText function and negates its return value. */ int __stdcall CustomSortProc(long Item1, long Item2, long ParamSort) { return -CompareText(((TListItem *)Item1)->Caption, ((TListItem *)Item2)->Caption); } void __fastcall TForm1::Button1Click(TObject *Sender) { ListView1->CustomSort(CustomSortProc, 0); } void __fastcall TForm1::FormCreate(TObject *Sender) { TListItem *ListItem; ListView1->ViewStyle = vsList; ListItem = ListView1->Items->Add(); ListItem->Caption = "Apples"; ListItem = ListView1->Items->Add(); ListItem->Caption = "Oranges"; ListItem = ListView1->Items->Add(); ListItem->Caption = "Pears"; }
/* This example shows how to use the OnColumnClick and OnCompare events of a list view to let users sort the columns in a report-style list view by clicking on the column headers. This requires a global variable to keep track of the column that was clicked. The OnColumnClick event handler sets the global variable to indicate the column to sort and calls AlphaSort: */ void __fastcall TForm1::FormCreate(TObject *Sender) { TListItem *Item; TListColumn *Column; const char imagenames[3][20] = { "C++ Image", "Borland Image", "Delphi Image"}; const char Col2Array[3][40] = { "Documentation for the C++ icon.", "Borland icon.", "Delphi icon." }; // Create a ListView item for each image in the ImageList ListView1->SmallImages = ImageList1; ListView1->LargeImages = ImageList1; for (int i = 0; i < ImageList1->Count; i++) { Item = ListView1->Items->Add(); Item->Caption = imagenames[i]; Item->ImageIndex = i; Item->SubItems->Add(Col2Array[i]); } // Create two columns to show during viewing as vsReport Column = ListView1->Columns->Add(); Column->Caption = "Column 1"; Column->Width = 200; Column = ListView1->Columns->Add(); Column->Caption = "Column 2"; Column->Width = 200; ListView1->ViewStyle = vsReport; } int ColumnToSort = 0; /* The OnColumnClick event handler sets the global variable to indicate the column to sort and calls AlphaSort: */ void __fastcall TForm1::ListView1ColumnClick(TObject *Sender, TListColumn *Column) { ColumnToSort = Column->Index; ((TCustomListView *)Sender)->AlphaSort(); } /* The OnCompare event handler causes the list view to sort on the selected column: */ void __fastcall TForm1::ListView1Compare(TObject *Sender, TListItem *Item1, TListItem *Item2, int Data, int &Compare) { if (ColumnToSort == 0) Compare = CompareText(Item1->Caption,Item2->Caption); else { int ix = ColumnToSort - 1; Compare = CompareText(Item1->SubItems->Strings[ix], Item2->SubItems->Strings[ix]); } }
Delphi Examples:
{ The following code orders a list view in reverse alphabetical order on the click of a button. The callback function CustomSortProc calls the global CompareText function and negates its return value. } function CustomSortProc(Item1, Item2: TListItem; ParamSort: integer): integer; stdcall; begin Result := -CompareText(Item1.Caption,Item2.Caption); end; procedure TForm1.Button1Click(Sender: TObject); begin ListView1.CustomSort(@CustomSortProc, 0); end; procedure TForm1.FormCreate(Sender: TObject); var ListItem : TListItem; begin ListView1.ViewStyle := vsList; ListItem := ListView1.Items.Add; ListItem.Caption := 'Apples'; ListItem := ListView1.Items.Add; ListItem.Caption := 'Oranges'; ListItem := ListView1.Items.Add; ListItem.Caption := 'Pears'; end;
{ This example shows how to use the OnColumnClick and OnCompare events of a list view to let users sort the columns in a report-style list view by clicking on the column headers. This requires a global variable to keep track of the column that was clicked. The OnColumnClick event handler sets the global variable to indicate the column to sort and calls AlphaSort: } var ColumnToSort: Integer; procedure TForm1.FormCreate(Sender: TObject); var I: Integer; ListItem: TListItem; NewColumn: TListColumn; const imagenames: Array[0..2] of string = ('C++ Image', 'Borland Image', 'Delphi Image'); begin Col2Array[0]:= 'Documentation for the C++ icon.'; Col2Array[1]:= 'Borland icon.'; Col2Array[2]:= 'Delphi icon.'; // Create a ListView item for each image in the ImageList with ListView1 do begin SmallImages := ImageList1; LargeImages := ImageList1; for I := 0 to ImageList1.Count - 1 do begin ListItem := Items.Add; Listitem.Caption := imagenames[I]; ListItem.ImageIndex := I; Listitem.SubItems.Add(Col2Array[I]); end; // Create two columns to show during viewing as vsReport NewColumn := Columns.Add; NewColumn.Caption := 'Column 1'; NewColumn.Width := 200; NewColumn := Columns.Add; NewColumn.Caption := 'Column 2'; NewColumn.Width := 200; ListView1.ViewStyle := vsReport; end; end; procedure TForm1.ListView1ColumnClick(Sender: TObject; Column: TListColumn); begin ColumnToSort := Column.Index; (Sender as TCustomListView).AlphaSort; end; { The OnCompare event handler causes the list view to sort on the selected column: } procedure TForm1.ListView1Compare(Sender: TObject; Item1, Item2: TListItem; Data: Integer; var Compare: Integer); var ix: Integer; begin if ColumnToSort = 0 then Compare := CompareText(Item1.Caption,Item2.Caption) else begin ix := ColumnToSort - 1; Compare := CompareText(Item1.SubItems[ix],Item2.SubItems[ix]); end; end; { Note: This OnCompare event handler uses the global CompareText function. An application may want to use AnsiCompareText, CompareStr, or AnsiCompareStr instead, depending on whether the comparison should be case-sensitive and whether the locale should be considered. }
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