错误:对象引用未设置为对象的实例

问题描述

我有一个程序:翻转图像"

来源:

I have a program : " flip images"

Source :

Imports System.IO
Public Class Form1
    Dim khoa As Boolean
    Dim danhsachbt(6) As Button
    Dim dshinh(6) As Image
    Dim ds1(6), ds2(6), clicks, sott(2), s As Integer
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        danhsachbt(1) = Button1
        danhsachbt(2) = Button2
        danhsachbt(3) = Button3
        danhsachbt(4) = Button4
        danhsachbt(5) = Button5
        danhsachbt(6) = Button6
        Label1.Text = 40
        NewGame()
        ''

    End Sub

    Public Sub Image()
        dshinh(ds1(1)) = My.Resources.a
     dshinh(ds1(2)) = My.Resources.a
     ds2(ds1(1)) = 1
        ds2(ds1(2)) = 1

        dshinh(ds1(3)) = My.Resources.b
dshinh(ds1(4)) = My.Resources.b
ds2(ds1(3)) = 2
        ds2(ds1(4)) = 2

        dshinh(ds1(5)) = My.Resources.c
 dshinh(ds1(6)) = My.Resources.c
ds2(ds1(5)) = 3
        ds2(ds1(6)) = 3

    End Sub
    Public Sub LoadBT()
        For i As Integer = 1 To 6
            danhsachbt(i).Visible = True
        Next
    End Sub
    Public Sub NewGame()
        Dim i, j, Rand As Integer
        clicks = 0
        For i = 1 To 6
            danhsachbt(i).Image = Nothing
        Next

        For i = 1 To 6
A1:
            Randomize()
            Rand = Int(6 * Rnd() + 1)

            'Kt neu co rui thi lam lai
            For j = 1 To i - 1
                If Rand = ds1(j) Then GoTo A1
            Next
            ds1(i) = Rand
        Next
        Image()
        LoadBT()
        ProgressBar1.Maximum = Label1.Text
        ProgressBar1.Value = ProgressBar1.Maximum

    End Sub

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        If khoa = False Then Exit Sub
        If sott(1) = 1 Then Exit Sub

        clicks += 1
        sott(clicks) = 1
        Button1.Image = dshinh(1)
        If clicks = 2 Then Timer1.Enabled = True

    End Sub

    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
        If khoa = False Then Exit Sub
        If sott(1) = 2 Then Exit Sub

        clicks += 1
        sott(clicks) = 2
        Button2.Image = dshinh(2)
        If clicks = 2 Then Timer1.Enabled = True
    End Sub

    Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click
        If khoa = False Then Exit Sub
        If sott(1) = 3 Then Exit Sub

        clicks += 1
        sott(clicks) = 3
        Button3.Image = dshinh(3)
        If clicks = 2 Then Timer1.Enabled = True
    End Sub

    Private Sub Button4_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button4.Click
        If khoa = False Then Exit Sub
        If sott(1) = 4 Then Exit Sub

        clicks += 1
        sott(clicks) = 4
        Button4.Image = dshinh(4)
        If clicks = 2 Then Timer1.Enabled = True
    End Sub

    Private Sub Button5_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button5.Click
        If khoa = False Then Exit Sub
        If sott(1) = 5 Then Exit Sub

        clicks += 1
        sott(clicks) = 5
        Button5.Image = dshinh(5)
        If clicks = 2 Then Timer1.Enabled = True
    End Sub
    Private Sub Button6_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button6.Click
        If khoa = False Then Exit Sub
        If sott(1) = 6 Then Exit Sub

        clicks += 1
        sott(clicks) = 6
        Button6.Image = dshinh(6)
        If clicks = 2 Then Timer1.Enabled = True
    End Sub

    Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick
        If clicks = 1 Then Exit Sub
        'KT hinh giong nhau
        If ds2(sott(1)) = ds2(sott(2)) Then
            danhsachbt(sott(2)).Visible = False
            danhsachbt(sott(1)).Visible = False
            MsgBox("co gang")
            'KT ket thuc game
            Dim i As Integer
            Dim Match As Boolean = True
            For i = 1 To 6
                If danhsachbt(i).Visible = True Then
                    Match = False
                    Exit For
                End If
            Next
            If Match = True And TextBox1.Text > 0 Then
                Timer2.Stop()
                ProgressBar1.Visible = True
                MsgBox("Chuc Mung! Ban Da Chien Thang", , "Thong Bao")
            End If
        Else
            danhsachbt(sott(1)).Image = Nothing
            danhsachbt(sott(2)).Image = Nothing
        End If
        sott(1) = 0
        sott(2) = 0
        clicks = 0
    End Sub
    Dim check As Boolean
    Private Sub Button7_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button7.Click
        ProgressBar1.Visible = False
        TextBox1.Text = Label1.Text
        s = TextBox1.Text
        khoa = True
        NewGame()
        Timer2.Start()
        check = True

    End Sub

    Private Sub Timer2_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer2.Tick
        TextBox1.Text = s - 1
        If ProgressBar1.Value <= ProgressBar1.Maximum And ProgressBar1.Value > 0 Then
            ProgressBar1.Value -= 1
        Else
            ProgressBar1.Value = 0
        End If
        s = s - 1
        If s = 0 Then
            Timer2.Stop()
            ProgressBar1.Visible = True
            MsgBox("Het Thoi Gian! Ban Da Thua", , "Thong Bao")
            khoa = False
        End If
    End Sub
End Class

在此出现错误对象引用未设置为对象的实例":
danhsachbt(sott(2)).Visible = False
请帮助我！

There is an error "Object reference not set to an instance of an object" in this :
danhsachbt(sott(2)).Visible = False
Please help me !

推荐答案

danhsachbt(1) = Button1
danhsachbt(2) = Button2
danhsachbt(3) = Button3
danhsachbt(4) = Button4
danhsachbt(5) = Button5
danhsachbt(6) = Button6

将上面的代码更改为

Change above code to

danhsachbt(0) = Button6
danhsachbt(1) = Button1
danhsachbt(2) = Button2
danhsachbt(3) = Button3
danhsachbt(4) = Button4
danhsachbt(5) = Button5

您还需要根据需要进行适当的更改，我的意思是现在您必须从0到5而不是1到6循环.

问候
鲁西(Rushi)

you also need to make appropriate changes where required, I mean now you have to loop from 0 to 5 not 1 to 6.

Regards
Rushi

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