Option Strict On
Option Explicit On
Imports System.Math
Public Class Form1
    'Функция ввода исходн. данных из  TextBox
    Function vvod(ByVal T As TextBox) As Double
        Return Val(T.Text)
    End Function

    'Процедура форматированного вывода результата  в TextBox
    Sub vivod(ByVal Z As Double, ByVal T As TextBox)
        T.Text = Format(Z, "00.0000")
    End Sub

    'Процедура форматированного вывода результата  в ListBox
    Sub vivodList(ByVal Z As Double, ByVal LB As ListBox)
        LB.Items.Add(Format(Z, "00.0000"))
    End Sub

    'Процедура вывода целого результата в TextBox
    Sub vivodint(ByVal Z As Integer, ByVal T As TextBox)
        T.Text = CStr(Z)
    End Sub
    Public Function Fun(ByVal x As Double) As Double
        Return 2 ^ (-x) * E ^ x
    End Function
    Public Sub RegCikl(ByVal a As Double, ByVal b As Double, _
                       ByVal h As Double, _
                       ByRef max As Double)
        Dim i As Integer, n As Integer, y As Double, x As Double
        n = CInt((b - a) / h + 1)
        vivodint(n, TextBox6)
        max = Double.MinValue
        For i = 1 To n
            y = Fun(x)
            If y > max Then
                max = y
            End If
            vivodList(x, ListBox1) : vivodList(y, ListBox2)
            x = x + h
        Next
    End Sub
    Private Sub Button1_Click(ByVal sender As System.Object, _
               ByVal e As System.EventArgs) Handles Button1.Click

        Dim a As Double, b As Double, h As Double

        Dim mm1 As Double
        a = vvod(TextBox4)
        b = vvod(TextBox5)
        h = vvod(TextBox6)
        RegCikl(a, b, h, mm1)
        vivod(mm1, TextBox9)

    End Sub
    Private Sub Button2_Click(ByVal sender As System.Object, _
                   ByVal e As System.EventArgs) Handles Button2.Click
        End
    End Sub

End Class