使用 LINQ 从 CSV 上传多条记录

Question

我正在尝试使用 CSV 文件向数据库 table 添加多条记录。如果我删除 try/catch，我会收到此错误：

System.IO.FileNotFoundException
HResult=0x80070002
Message=Could not find file 'C:\Program Files (x86)\IIS Express\BJ_and_TS.csv'.
Source=<Cannot evaluate the exception source>
StackTrace:
<Cannot evaluate the exception stack trace>

为什么不保存文件？我还做错了什么？这是我的代码隐藏：

Private Sub BTN_Upload_Click(sender As Object, e As EventArgs) Handles BTN_Upload.Click
    Dim context As New MusicContext
    Try
        If FU_CSV.HasFile Then
            FU_CSV.SaveAs(Server.MapPath("~/Content/Docs/Data/" & FU_CSV.FileName))
            Dim csvData = From line As String In File.ReadAllLines(FU_CSV.FileName)
                          Skip 1
                          Let CR = line.Split(",")
                          Select New Album With {
                    .AlbumName = CR(0),
                    .ImagePath = CR(1),
                    .ReleaseDate = CDate(CR(2)),
                    .UnitPrice = CDec(CR(3)),
                    .BandID = CInt(CR(4)),
                    .GenreID = CInt(CR(5))
                }
            For Each a As Album In csvData
                context.Albums.Add(a)
                context.SaveChanges()
            Next

            'ClientScript.RegisterStartupScript(Page.GetType(), "BulkAlbums", "$('#BulkRecords').modal();", True)
        End If
    Catch ex As Exception

    End Try
End Sub

Answer 1

您正在保存包含路径的文件，但随后试图仅使用文件名访问它。然后代码尝试从运行目录访问该文件作为默认目录，而不是您保存文件的目录，这就是为什么您收到错误路径的 "could not find file" 错误。

您应该可以通过在调用 File.ReadAllLines:

时指定完整路径来解决此问题

Dim filenameWithPath as string = Server.MapPath("~/Content/Docs/Data/" & FU_CSV.FileName)

FU_CSV.SaveAs(filenameWithPath)
Dim csvData = From line As String In File.ReadAllLines(filenameWithPath)

使用 LINQ 从 CSV 上传多条记录

Uploading Multiple Records from a CSV using LINQ

linq

vb.net

asp.net

webforms