vba中，按照书上用（if then...else)编了一个小程序，为什么返回不了正确值？

• Sub 判别构成三角形() '该程序有错误，无法返回正确值
• Dim a As Double, b As Double, c As Double
• Dim area As Double, s As Double
• Dim flagu As Boolean, flagl As Boolean
• a = CDbl(InputBox("请输入三角形的第1条边", "求三角形面积", 0))
• b = CDbl(InputBox("请输入三角形的第2条边", "求三角形面积", 0))
• c = CDbl(InputBox("请输入三角形的第3条边", "求三角形面积", 0))
• flagu = ((a + b) > c) And ((a + c) > b) And ((b + c) > a)
• flagl = ((a - b) < c) And ((a - c) < b) And ((b - c) < a)
• If (falgu And flagl) Then
• s = (a + b + c) / 2
• area = Math.Sqr(s * (s - a) * (s - b) * (s - c))
• MsgBox "三角形的三边分别为：a=" & a & "，b=" & b & "，c=" & c & "。面积area=" & area, vbOKOnly, "求三角形的面积"
• Else
• MsgBox "边长：a=" & a & "，b=" & b & "，c=" & c & "。不能构成三角形", vbOKOnly, "判断三条边是否可构成三角形"
• End If
• End Sub

因为一个地方写错了，If (falgu And flagl) Then应为If (flagu And flagl) Then ，flagu错写为falgu

(falgu And flagl)中，变量falgu书写错误，应为flagu。修改后测试正确。