LineStyle Property [Excel 2003 VBA Language Reference]

XlLineStyle

XlLineStyle can be one of these XlLineStyle constants.
xlContinuous
xlDash
xlDashDot
xlDashDotDot
xlDot
xlDouble
xlSlantDashDot
xlLineStyleNone

expression.LineStyle

expression Required. An expression that returns one of the objects in the Applies To list.

Example

This example puts a border around the chart area and the plot area of Chart1.

With Charts("Chart1")
    .ChartArea.Border.LineStyle = xlDashDot
    With .PlotArea.Border
        .LineStyle = xlDashDotDot
        .Weight = xlThick
    End With
End With

Applies to | Border Object | Borders Collection