The DateChange event is fired when the first visible date is changed. Use the FirstVisibleDate property to specify the first visible date. Use the ScrollTo method to ensure that a specified date is visible. Use the FormatDate property to format a date to a specified format.

The following VB sample displays the first visible date when the user changes the first visible date:

Private Sub G2antt1_DateChange()
    With G2antt1.Chart
        Debug.Print FormatDateTime(.FirstVisibleDate)
    End With
End Sub

The following VB sample limits the scrolling area of the chart from 1/1/2005 to 31/12/2005:

Private Function LastVisibleDate(ByVal g As EXG2ANTTLibCtl.G2antt) As Date
    With G2antt1
        With .Chart
            Dim d As Date
            d = .FirstVisibleDate
            Do While .IsDateVisible(d)
                d = .NextDate(d, exDay, 1)
            Loop
        End With
    End With
    LastVisibleDate = d - 1
End Function

Private Sub G2antt1_DateChange()
    Dim dMin As Date, dMax As Date
    dMin = "1/1/2005"
    dMax = "31/12/2005"
    With G2antt1.Chart
        If .FirstVisibleDate < dMin Then
            .FirstVisibleDate = dMin
        End If
        If LastVisibleDate(G2antt1) > dMax Then
            .FirstVisibleDate = dMax - (LastVisibleDate(G2antt1) - .FirstVisibleDate) + 1
        End If
    End With
End Sub

or you can use the FormatDate method like follows:

Private Sub G2antt1_DateChange()
    With G2antt1.Chart
        Debug.Print .FormatDate(.FirstVisibleDate, "<%yyyy%>-<%m%>-<%d%>")
    End With
End Sub

The following C++ sample displays the first visible date when the user changes the first visible date:

#include "G2antt.h"
#include "Chart.h"

static DATE V2D( VARIANT* pvtDate )
{
	COleVariant vtDate;
	vtDate.ChangeType( VT_DATE, pvtDate );
	return V_DATE( &vtDate );
}

void OnDateChangeG2antt1() 
{
	if ( m_g2antt.GetControlUnknown() )
	{
		CChart chart = m_g2antt.GetChart();
		TCHAR szDate[1024] = _T("");
		SYSTEMTIME stDate = {0};
		VariantTimeToSystemTime( V2D( &chart.GetFirstVisibleDate() ), &stDate );
		GetDateFormat( LOCALE_SYSTEM_DEFAULT, LOCALE_USE_CP_ACP, &stDate, NULL, szDate, 1024 );
		OutputDebugString( szDate );
	}
}

The following VB.NET sample displays the first visible date when the user changes the first visible date:

Private Sub AxG2antt1_DateChange(ByVal sender As Object, ByVal e As System.EventArgs) Handles AxG2antt1.DateChange
    Debug.Write(AxG2antt1.Chart.FirstVisibleDate.ToString())
End Sub

The following C# sample displays the first visible date when the user changes the first visible date:

private void axG2antt1_DateChange(object sender, EventArgs e)
{
	System.Diagnostics.Debug.Write(axG2antt1.Chart.FirstVisibleDate.ToString());
}

The following VFP sample displays the first visible date when the user changes the first visible date:

*** ActiveX Control Event ***

with thisform.G2antt1.Chart
	wait window nowait .FormatDate(.FirstVisibleDate, "<%yyyy%>-<%m%>-<%d%>")
endwith

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