Question

我创建了一个tiff查看器，它已经可以查看tiff图像了。除非它的分辨率高达1200 DPI。我的代码中是否有导致问题的解决方法？

 Public Function GetTiffImage(path As String, page As Integer) As Image


        Dim ms As MemoryStream = Nothing
        Dim SrcImg As Image = Nothing
        Dim returnImage As Image = Nothing

        Try
            SrcImg = Image.FromFile(path)
            ms = New MemoryStream()
            Dim FrDim As New FrameDimension(SrcImg.FrameDimensionsList(0))
            SrcImg.SelectActiveFrame(FrDim, Page)
            SrcImg.Save(ms, ImageFormat.Tiff)
            returnImage = Image.FromStream(ms)
        Catch ex As Exception
            Throw ex
        Finally
            SrcImg.Dispose()
            GC.Collect()
            GC.WaitForPendingFinalizers()
        End Try

        Return returnImage
    End Function

提前致谢

Answer 1

根据我的经验，此错误消息具有误导性，通常由OutOfMemoryException引起。我打赌你因为没有清理所有IDisposable对象而失去记忆力。我知道GC.Collect()不一定是可靠的方法。尝试放入一些using块。我使用C＃而不是VBScript，因此无法提供确切的语法，但在C＃中它是这样的：

using (var SrcImg = Image.FromFile(path))
{
  using (var ms = MemoryStream())
  {
    var FrDim = new FrameDimension(SrcImg.FrameDimensionsList(0));
    SrcImg.SelectActiveFrame(FrDim, Page)
    SrcImg.Save(ms, ImageFormat.Tiff)
    using (var returnImage = Image.FromStream(ms))
    {
      return returnImage;
    }
  }
}

Answer 2

处理图像后需要释放的内存以防止内存泄漏。这个基于代码的样本代码已被修改以防止内存泄漏。

Public Function GetTiffImage(path As String, page As Integer) As Image
    Using ms As New MemoryStream
        Using SrcImg As Image = Image.FromFile(path)
            Using returnImage As Image = Image.FromStream(ms)
                Try
                    Dim FrDim As New FrameDimension(SrcImg.FrameDimensionsList(0))
                    SrcImg.SelectActiveFrame(FrDim, page)
                    SrcImg.Save(ms, ImageFormat.Tiff)
                Catch ex As Exception
                    Throw ex
                End Try
                Return returnImage
            End Using
        End Using
    End Using
End Function

观看1200 Dpi Tiff图像时GDI +中发生一般错误

2 个答案: