TStringBuilderClickCount (C++)

Description

This code demonstrates the use of the TStringBuilder class to build strings in a simple way. The example calculates the number of times the user pressed a button. Example assumes that you have a button on a form and a private variable called m_clickCount.

Code

void __fastcall TMainForm::Button1Click(TObject *Sender)
{
        /* Increase the click count for the button. */
        m_clickCount++;
 
        /* Create a new instance of TStringBuilder. */
        TStringBuilder* sb = new TStringBuilder();
 
        /* Append the message to the string builder. */
        sb->Append("This button was pressed ")->
                AppendFormat("%d times", ARRAYOFCONST((m_clickCount)));
 
        /* Show a message; use ToString to access the built string. */
        MessageDlg(sb->ToString(), mtInformation, TMsgDlgButtons() << mbOK, 0);
 
        /* Clear the string builder to allow building another string. */
        sb->Clear();
 
        if (sb->Length != 0)
                MessageDlg("This cannot happen! Length must be 0 after clear!", mtError,
                        TMsgDlgButtons() << mbOK, 0);
 
        /* Build another string with 2 lines. */
        TButton *button = dynamic_cast<TButton *>(Sender);
        sb->Append("The name of the button was:")->
                AppendLine()->
                        Append(button->Name);
 
        /* Show another message and free the string builder instance. */
        MessageDlg(sb->ToString(), mtInformation, TMsgDlgButtons() << mbOK, 0);
        delete sb;
}

Uses

• System.SysUtils.TStringBuilder ( fr | de | ja )
• System.SysUtils.TStringBuilder.Append ( fr | de | ja )
• System.SysUtils.TStringBuilder.AppendFormat ( fr | de | ja )
• System.SysUtils.TStringBuilder.AppendLine ( fr | de | ja )
• System.SysUtils.TStringBuilder.Clear ( fr | de | ja )
• System.SysUtils.TStringBuilder.Create ( fr | de | ja )
• System.SysUtils.TStringBuilder.Length ( fr | de | ja )
• System.SysUtils.TStringBuilder.ToString ( fr | de | ja )

See Also

• dynamic_cast (C++ Type Cast Operator)