RAD Studio VCL Reference
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Indicates whether a particular item is selected.
property Selected: TColor;
__property TColor Selected;
Use Selected to query the state of a particular item in the list box. If the item specified by the Index parameter is selected in the list box, the value of the Selected property is true. If the specified item is not selected, Selected is false. Set Selected to change the currently selected item.
The Index parameter is the item referenced by its position in the list box, with the first item having an Index value of 0.
An item is selected when the user highlights it. More than one item in the list box can be selected by setting the MultiSelect property to true. In this case, the Selected item is the one that has focus when the list box has input focus.
C++ Examples:
/* This example uses a file listbox and a regular listbox on a form. The following routine scans through the files listed in the file listbox and lists the sizes of any selected files to the regular list box. To exercise the error condition create a file in the Debug directory, start this application and then delete the file. Now try to list the size of the deleted file. Continue will continue listing file sizes in a multiple selection that includes the deleted file. Break will stop. Set the MultiSelect and ExtendedSelect properties on the FileListBox. */ #include <stdio.h> // for FILE, fopen, fstat, fileno, fread and fclose #include <sys\stat.h> // for fstat and the stat struct void __fastcall TForm1::Button1Click(TObject *Sender) { for (int i = 0; i < FileListBox1->Items->Count; i++) { if (FileListBox1->Selected[i]) { if (!FileExists(FileListBox1->Items->Strings[i])) { MessageBeep(0); if (Application->MessageBox( AnsiString("File " + FileListBox1->Items->Strings[i] + "not found").c_str(), NULL, MB_OKCANCEL) == IDCANCEL) break; else continue; } FILE *F = fopen(FileListBox1->Items->Strings[i].c_str(),"r"); struct stat statbuf; fstat(fileno(F), &statbuf); ListBox1->Items->Add( FileListBox1->Items->Strings[i] + ": " + IntToStr(statbuf.st_size)); fclose(F); } } }
Delphi Examples:
{ This example uses a file listbox and a regular listbox on a form. The following routine scans through the files listed in the file listbox and lists the sizes of any selected files to the regular list box. To exercise the error condition create a file in the Debug directory, start this application and then delete the file. Now try to list the size of the deleted file. Set the MultiSelect and ExtendedSelect properties on the FileListBox. } procedure TForm1.Button1Click(Sender: TObject); var F: File; i, filehandle: Integer; begin for i := 0 to (FileListBox1.Items.Count - 1) do begin try if FileListBox1.Selected[i] then begin if not FileExists(FileListBox1.Items.Strings[i]) then begin MessageDlg('File: ' + FileListBox1.Items.Strings[i] + ' not found', mtError, [mbOk], 0); Continue; end; filehandle:= FileOpen(FileListBox1.Items.Strings[i], 1); if (filehandle = -1) then begin MessageDlg('File: ' + FileListBox1.Items.Strings[i] + ' cannot be opened with access mode 1.', mtError, [mbOk], 0); Continue; end else FileClose(filehandle); AssignFile(F, FileListBox1.Items.Strings[i]); Reset(F, 1); ListBox1.Items.Add( FileListBox1.Items.Strings[i] + ': ' + IntToStr(FileSize(F))); CloseFile(F); end; finally { do something here } end; end; end;
Copyright(C) 2008 CodeGear(TM). All Rights Reserved.
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