如何将图片从图片盒保存为jpg

Question

我已经可以将文件另存为.jpeg，但是图像无法加载，有人建议吗？

    Private Sub Btnconfirm_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Btnconfirm.Click

        MsgBox("A receipt will now be saved to your files", vbOKOnly, "Thank you for your purchase")

        SaveFileDialog1.ShowDialog()
        MsgBox("Thank you for choosing Tiny Theatre, have a nice day.", vbOKOnly, "Thank you")
        Me.Close()
    End Sub

    Private Sub SaveFileDialog1_FileOk(ByVal sender As System.Object, ByVal e As System.ComponentModel.CancelEventArgs) Handles SaveFileDialog1.FileOk
        Dim FileToSaveAs As String = SaveFileDialog1.FileName

        Dim objwriter As New System.IO.StreamWriter(FileToSaveAs)
        objwriter.Write(PictureBox1)
        objwriter.Close()
    End Sub

Answer 1

没有尝试过，但是可以这样做吗？

Private Sub SaveFileDialog1_FileOk(ByVal sender As System.Object, ByVal e As System.ComponentModel.CancelEventArgs) Handles SaveFileDialog1.FileOk
    Dim FileToSaveAs As String = System.IO.Path.Combine(My.Computer.FileSystem.SpecialDirectories.Temp, SaveFileDialog1.FileName)
    PictureBox1.Image.Save(FileToSaveAs, System.Drawing.Imaging.ImageFormat.Jpeg)
End Sub

如果需要设置编码器参数（如jpeg压缩），则需要Save方法的重载。请参阅http://msdn.microsoft.com/en-us/library/system.windows.forms.picturebox.image.aspx和http://msdn.microsoft.com/en-us/library/system.drawing.image .aspx

所提供的代码将图片框控件以序列化的形式保存到扩展名为jpeg的文件中。将text.txt文件重命名为text.jpg不会使其成为有效的jpg图像。是一样的