VB虽说不再是当今编程语言的主流，但VB所拥有图形用户界面（GUI）和快速应用程序开发（RAD）系统，可以让我们轻松的使用VB提供的组件快速建立一个应用程序。下面我们一起来做一个小程序，回味经典。

界面设计：

程序运行效果图

各项参数设置

代码设计：

Public Class Form1

Dim a As Single, p As Single

Dim b As Single, s As Single

Dim c As Single

Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click

a = Val(TextBox1.Text)

b = Val(TextBox2.Text)

c = Val(TextBox3.Text)

p = (a + b + c) / 2

s = Math.Sqrt(p * (p - a) * (p - b) * (p - c))

TextBox4.Text = Str(s)

End Sub

Private Sub TextBox1_TextChanged(sender As Object, e As EventArgs) Handles TextBox1.TextChanged

End Sub

Private Sub TextBox2_TextChanged(sender As Object, e As EventArgs) Handles TextBox2.TextChanged

End Sub

Private Sub TextBox3_TextChanged(sender As Object, e As EventArgs) Handles TextBox3.TextChanged

End Sub

Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click

TextBox1.Text = ""

TextBox2.Text = ""

TextBox3.Text = ""

TextBox4.Text = ""

End Sub

Private Sub TextBox4_TextChanged(sender As Object, e As EventArgs) Handles TextBox4.TextChanged

End Sub

Private Sub Button3_Click(sender As Object, e As EventArgs) Handles Button3.Click

End

End Sub

End Class

运行结果：

运行结果图

最后多说一句，没有过时的程序语言，只要能满足工作需要就是好的语言。