Question

我正在使用vb.net开发一个asp.net webforms网站。在gridview中显示为链接的文件列表中，单击链接时，它会调用OpenFile方法。我在网上找到的这个代码用于将存储在webserver中的文件下载到客户端，这适用于图像，但是当我尝试下载.docx或.xlsx文件时，它会出错在"Response.BinaryWrite(btFile)"行，但下载文件。下面给出的是实际代码的短版本

页码：

Protected Sub grvItemAttachments_RowCommand(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.GridViewCommandEventArgs) Handles grvItemAttachments.RowCommand
    Try
        If e.CommandName = "Open" Then
            FileOpener.OpenFile(fileNameWithPath)
        End If
    Catch ex As Exception
        ErrHandler.WriteError(ex.Message)
    End Try
 End Sub

文件打开器代码：

Public Shared Sub OpenFile(fileNameWithPath as string)
    Dim file As New FileInfo(fileNameWithPath)
    Dim fs As System.IO.FileStream = Nothing
    fs = System.IO.File.Open(fileNameWithPath, System.IO.FileMode.Open)
    Dim btFile As Byte() = New Byte(fs.Length - 1) {}
    fs.Read(btFile, 0, Convert.ToInt32(fs.Length))
    fs.Close()
    Response.AddHeader("Content-disposition", "attachment; filename=" & FileName)
    Response.ContentType = GetFileType(file.Extension.ToLower()) 
    Response.BinaryWrite(btFile)
    Response.End()
End Sub

错误讯息：

System.ArgumentOutOfRangeException: Specified argument was out of the range of valid values." & vbCrLf & "Parameter name: offset" & vbCrLf & "   at System.Web.HttpResponseStream.Write(Byte[] buffer, Int32 offset, Int32 count)" & vbCrLf & "   at System.Web.HttpResponse.BinaryWrite(Byte[] buffer)" & vbCrLf & "   at FileOpener.OpenFile(String FileName, String FolderName) in D:\Projects\VSS Projects\PIL WebSite\App_Code\Common\FileOpener.vb:line 25" & vbCrLf & "   at Web_RTOView.grvItemAttachments_RowCommand(Object sender, GridViewCommandEventArgs e) in D:\Projects\VSS Projects\PIL WebSite\Web\RTOView.aspx.vb:line 310}
------
grvItemAttachments_RowCommand
Error Message: Specified argument was out of the range of valid values.
Parameter name: offset

知道如何解决这个问题吗？

Answer 1

为什么要将字节数组初始化为Length-1？不应该是长度的确切大小？实际上，您尝试将文件的内容从0读取到Length但您的字节数组length为Length-1

Response.BinaryWrite（）中的System.ArgumentOutOfRangeException

1 个答案: