如何在讀取檔案時擺脫vb.net中的空行

下面是從 .CSV 檔案中讀取資料的代碼，該檔案有 3 列（不斷變化）。有時，當用戶在 Excel 中打開 .csv 并洗掉其中的一行時，該行會被讀取為空行或空格行，并以逗號分隔。

當通過代碼讀取相同的內容時，我得到“，”作為輸入，它作為空行添加到我的資料表中。我怎樣才能逃脫這個空白行？

Dim sreader As StreamReader
Dim sstring As String
Dim dt As DataTable
Dim counter as Integer
sreader = File.OpenText(Path.ToString) 'this path is path of the excel
    
While sreader.Peek <> -1

    sstring = sreader.Readline()
    If sstring <> " " then  ' how can I check here that the string does not have any content in it except for the seperating commas
    Dim str As String () = sstring.Split(",")
    
    
    Dim rowdt As DataRow
    rowdt = dt.NewRow()
    
    For i As Integer = 0 To dt.Columns.count-1
        rowdt(i) = str(i).ToString()
    Next

    dt.rows.Add(rowdt)
    End if
Counter = counter   1
End While

我嘗試了一些東西。已在答案部分發布

這是我試過的

Dim sreader As StreamReader
Dim counter as Integer
Dim sstring As String
Dim dt As DataTable
sreader = File.OpenText(Path.ToString) 

 While sreader.Peek <> -1

 sstring = sreader.Readline()

 Dim no as integer = 0

 For each str as String in sstring.Split(",")
  If str.ToString.Trim = "" then
   no = no   1
   End If
  Next


  If no <> 3 then 
 Dim str As String () = sstring.Split(",")


 Dim rowdt As DataRow
 rowdt = dt.NewRow()

  For i As Integer = 0 To dt.Columns.count-1
rowdt(i) = str(i).ToString()
Next

 dt.rows.Add(rowdt)
 End if
 End if
counter = counter   1
End While

uj5u.com熱心網友回復：

讀取所有行，然后只處理逗號之間有任何值的行

Dim path = "filename.txt"
Dim dt As New DataTable()
dt.Columns.AddRange(
    {
        New DataColumn("Column1"), New DataColumn("Column2"),
        New DataColumn("Column3"), New DataColumn("Column4"),
        New DataColumn("Column5"), New DataColumn("Column6"),
        New DataColumn("Column7"), New DataColumn("Column8"),
        New DataColumn("Column9"), New DataColumn("Column10")
    })

Dim sw As New Stopwatch()
sw.Start()

Dim lines = File.ReadAllLines(Path)
For Each line In lines
    Dim split = line.Split({","c}, StringSplitOptions.None)
    If split.Any(Function(s) Not String.IsNullOrWhiteSpace(s)) Then
        Dim row = dt.NewRow()
        For i As Integer = 0 To dt.Columns.Count - 1
            row(i) = split(i).ToString()
        Next
        dt.Rows.Add(row)
    End If
Next

sw.Stop()
Console.WriteLine($"Took {sw.ElapsedMilliseconds} ms")
Console.WriteLine($"Read {dt.Rows.Count()} rows")

經過測驗以解決性能問題

檔案內容 1024 行a,b,c,d,e,f,g,h,i,j和一些,,,,,,,,,混合的行，包括檔案的最后一行

檔案的最后10 行：

A，B，C，d，E，F，G，H，I，J
，A，B，C，d，E，F，G，H，I，J
,,,,,,,,,
,,, ,,,,,,
a,b,c,d,e,f,g,h,i,j
a,b,c,d,e,f,g,h,i,j
,,,,,, ,,,
a,b,c,d,e,f,g,h,i,j
a,b,c,d,e,f,g,h,i,j
,,,,,,,,,,

StopWatch 物件顯示讀取所有行需要 2 毫秒。并且在生成的 DataTable 中正好有 1024 行資料。處理器跳過沒有值的行

花了 2 毫秒
讀取 1024 行

uj5u.com熱心網友回復：

我試過拆分和檢查字串。希望它有效。

Dim sreader As StreamReader
Dim counter as Integer
Dim sstring As String
Dim dt As DataTable
sreader = File.OpenText(Path.ToString) 

While sreader.Peek <> -1

    sstring = sreader.Readline()

    Dim no as integer = 0

    For each str as String in sstring.Split(",")
        If str.ToString.Trim = "" then
            no = no   1
        End If
    Next

    If no <> 3 then 
        Dim str As String () = sstring.Split(",")

        Dim rowdt As DataRow
        rowdt = dt.NewRow()

        For i As Integer = 0 To dt.Columns.count-1
            rowdt(i) = str(i).ToString()
        Next

        dt.rows.Add(rowdt)
    End if
    End if
    counter = counter   1
End While

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