This VCL application first creates a list of strings. Then it iterates through the strings, changing all string characters to uppercase. It consists of the following steps:
- Create a VCL Form with Buttons and TListBox controls.
- Write the code to create a string list and add strings to it.
- Write the code to iterate through the string list to process string characters.
- Run the application.
To create a VCL Form with TButton and TListBox controls
- Choose FileNewOtherDelphi Projects or C++Builder Projects and double-click the VCL Forms Application icon. The VCL Forms Designer is displayed.
- From the Standard page of the Tool palette, place two TButtons and a TListBox component on the form.
- Select Button1 on the form.
- In the Object Inspector, enter Add for the Name and Caption properties.
- Select Button2 on the form.
- In the Object Inspector, enter ToUpper for the Name and Caption properties.
To create a string list and add strings to it
- Select the Add button on the form.
- In the Object Inspector, double-click the OnClick action on the Events tab. The Code Editor displays, with the cursor in the TForm1.AddClick (Delphi) or TForm1::AddClick (C++) event handler block.
- For Delphi, place the cursor before the begin reserved word; then press ENTER. This creates a new line above the code block.
- For Delphi, insert the cursor on the new line created, and type the following variable declaration:
- Insert the cursor within the code block, and type the following code:
MyList := TStringList.Create;
try
with MyList do
begin
Add('Mice');
Add('Goats');
Add('Elephants');
Add('Birds');
ListBox1.Items.AddStrings(MyList);
end;
finally
MyList.Free;
end;
TStringList *MyList = new TStringList();
try {
MyList->Add(“Mice”);
MyList->Add(“Goats”);
MyList->Add(“Elephants”);
MyList->Add(“Birds”);
ListBox1–>Items->AddStrings( MyList );
} __finally {
MyList->Free();
}
To change all characters to uppercase
- Select the ToUpper button on the form.
- In the Object Inspector, double-click the OnClick action on the Events tab. The Code Editor displays, with the cursor in the TForm1.ToUpperClick (Delphi) or TForm1::ToUpperClick (C++) event handler block.
- For Delphi, place the cursor before the begin reserved word; then press return. This creates a new line above the code block.
- For Delphi, insert the cursor on the new line created and type the following variable declaration:
- Insert the cursor within the code block, and type the following code:
for Index := 0 to ListBox1.Items.Count - 1 do
ListBox1.Items[Index] := UpperCase(ListBox1.Items[Index]);
for( int i = 0; i < ListBox1–>Items->Count; i++ ) {
ListBox1–>Items[i] = UpperCase( ListBox1–>Items[i] );
}
To run the application
- Save your project files; then choose RunRun to build and run the application. The form displays with the controls.
- Click the Add button. The strings 'Mice', 'Goats', 'Elephants', and 'Birds' display in the order listed.
- Click the ToUpper button. The string characters display in uppercase.