返回或设置指定线段起点一端的箭头长度。MsoArrowheadLength，可读写。
| MsoArrowheadLength 可以是下列常量之一： |
| msoArrowheadLengthMixed |
| msoArrowheadShort |
| msoArrowheadLengthMedium |
| msoArrowheadLong |
expression.BeginArrowheadLength
expression 必需。该表达式返回“应用于”列表中的一个对象。
本示例为活动的文档添加一条线段。直线的起点有一个短且窄的椭圆，终点有一个长且宽的三角形。
Dim docActive As Document
Set docActive = ActiveDocument
With docActive.Shapes.AddLine(100, 100, 200, 300).Line
.BeginArrowheadLength = msoArrowheadShort
.BeginArrowheadStyle = msoArrowheadOval
.BeginArrowheadWidth = msoArrowheadNarrow
.EndArrowheadLength = msoArrowheadLong
.EndArrowheadStyle = msoArrowheadTriangle
.EndArrowheadWidth = msoArrowheadWide
End With