四則運算(簡單版)

Public Class Form1
    Dim a, b
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        a = Val(TextBox1.Text)
        b = Val(TextBox2.Text)
        TextBox3.Text = a + b
    End Sub

    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
        a = Val(TextBox1.Text)
        b = Val(TextBox2.Text)
        TextBox3.Text = a - b
    End Sub

    Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click
        a = Val(TextBox1.Text)
        b = Val(TextBox2.Text)
        TextBox3.Text = a * b
    End Sub

    Private Sub Button4_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button4.Click
        a = Val(TextBox1.Text)
        b = Val(TextBox2.Text)
        TextBox3.Text = a / b
    End Sub
End Class