为什么当我处理表单并再次返回时 openFileDialog 没有响应？

Question

I have tow openFileDialog tools in one form, when i browse openFileDialog1 and choose a picture, it's ok but when i dispose this form and back to it and click to browse another picture, it doesn't responding and the project stopped with no errors!!!

    Private Sub Browse_Click(sender As Object, e As EventArgs) Handles Browse.Click
        OpenFileDialog1.FileName = ""
        OpenFileDialog1.Filter = "Image Files (*.jpg, *.bmp, *.gif, *.png)|*.jpg; *.bmp; *.gif; *.png"
        If OpenFileDialog1.FileName = "" Then
            If OpenFileDialog1.ShowDialog() = Windows.Forms.DialogResult.OK Then
                txtFileName.Text = OpenFileDialog1.FileName
                txtFileName.SelectionStart = txtFileName.Text.Length 'to show the last portion of text
                If Trim(txtFileName.Text) <> "" Then picSave.Image = Image.FromFile(txtFileName.Text)
            End If
        Else
            Exit Sub
        End If
    End Sub

    Private Sub Btnclose_Click(sender As Object, e As EventArgs) Handles Btnclose.Click
        Me.Dispose()
    End Sub

Answer 1

In Project Properties be sure you have set Shutdown Mode to "When last form closes." This is NOT the default.

In Form1

Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
    OpenFileDialog1.Filter = "Image Files (*.jpg, *.bmp, *.gif, *.png)|*.jpg; *.bmp; *.gif; *.png"
    If OpenFileDialog1.ShowDialog() = DialogResult.OK Then
        TextBox1.Text = OpenFileDialog1.FileName
        PictureBox1.Image = Image.FromFile(TextBox1.Text)
    End If
End Sub

Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
    Form2.Show()
    Close()
End Sub

And then in Form2

Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
    Form1.Show()
    Close()
End Sub

When I return to Form1 the OpenFileDialog behaves normally.