當我從網站上下載Excel文件時，我無法看到它的內容

Question

我在Asp.net中有一個網站，其中我已經實現了一個按鈕，以Excel格式存儲GridView，但是當我打開文件時我無法看到GridView的實際內容，我只能看到列標題。在通過NuGet Package Manager安裝EPPlus後，我已經使用了三個以下導入。

using OfficeOpenXml; 
using System.IO; 
using WebFormsTest.Models; 

我後面的代碼如下所示

Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs) 
    If Not IsPostBack Then 
     Dim GetProducts As Object = Nothing 
     GridView6.DataSource = GetProducts 
     GridView6.DataBind() 
    End If 

End Sub 

Protected Sub Button3_Click(ByVal sender As Object, ByVal e As EventArgs) Handles Button3.Click 

    Response.Clear() 
    Dim products = GetProducts() 
    GridView6.DataSource = products 
    GridView6.DataBind() 
    Dim excel As ExcelPackage = New ExcelPackage 
    Dim workSheet = excel.Workbook.Worksheets.Add("Products") 
    Dim totalCols = GridView6.Rows(0).Cells.Count 
    Dim totalRows = GridView6.Rows.Count 
    Dim headerRow = GridView6.HeaderRow 
    worksheet.Cells["A1"].LoadFromCollection(GetProducts()) 
    Dim memoryStream = New MemoryStream 
    Response.ContentType = "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet" 
    Response.AddHeader("content-disposition", "attachment; filename=products.xlsx") 
    excel.SaveAs(memoryStream) 
    memoryStream.WriteTo(Response.OutputStream) 
    Response.Flush() 
    Response.End() 
End Sub 



Public Function GetProducts() As List(Of Product) 

End Function 

我的aspx按鈕低於

<asp:Button ID="Button3" runat="server" Text="EXPORT RTD TO EXCEL" onclick="Button3_Click" BackColor="#FF9966" CssClass="btn btn-large" Font-Bold="True"/> 

Answer 1

編輯通過NuGet包管理器背後以下解決了這一問題，並在代碼中我們可以下載ClosedXML以便它包括以下進口

Imports ClosedXML.Excel 


Protected Sub Button3_Click(ByVal sender As Object, ByVal e As EventArgs) Handles Button3.Click 
    Dim dt As New DataTable("GridView_Data") 
    For Each cell As TableCell In GridView5.HeaderRow.Cells 
     dt.Columns.Add(cell.Text) 
    Next 
    For Each row As GridViewRow In GridView5.Rows 
     dt.Rows.Add() 
     For i As Integer = 0 To row.Cells.Count - 1 
      dt.Rows(dt.Rows.Count - 1)(i) = row.Cells(i).Text 
     Next 
    Next 
    Dim wb As New XLWorkbook 
    wb.Worksheets.Add(dt) 
    Response.Clear() 
    Response.Buffer = True 
    Response.Charset = "" 
    Response.ContentType = "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet" 
    Response.AddHeader("content-disposition", "attachment;filename=GridViewPOLQA.xlsx") 
    Using MyMemoryStream As New MemoryStream() 
     wb.SaveAs(MyMemoryStream) 
     MyMemoryStream.WriteTo(Response.OutputStream) 
     Response.Flush() 
     Response.[End]() 
    End Using 
End Sub 

Answer 2

給出我不知道的數據類型是什麼products，但爲什麼不綁定它直接表單？

worksheet.Cells["A1"].LoadFromCollection(GetProducts()); 

因爲你要發送一個Excel文件到客戶端（通過設置Response.ContentType），不要在那裏的GridView已經充滿了products更新的HTML頁面，你是不是在Button3_Click看到GridView控件的內容。

快速演示從C＃轉換到VB

Dim excelPackage As ExcelPackage = New ExcelPackage 
Dim worksheet As ExcelWorksheet = excelPackage.Workbook.Worksheets.Add("Sheet 1") 

worksheet.Cells("A1").LoadFromCollection(GetProducts()) 

Dim bin() As Byte = excelPackage.GetAsByteArray 

Response.ClearHeaders 
Response.Clear 
Response.Buffer = true 
Response.ContentType = "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet" 
Response.AddHeader("content-length", bin.Length.ToString) 
Response.AddHeader("content-disposition", "attachment; filename=""mySheet.xlsx"""")", Response.OutputStream.Write(bin, 0, bin.Length)) 
Response.Flush 
HttpContext.Current.ApplicationInstance.CompleteRequest