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我有一个包含逗号分隔文本的字符串。逗号分隔的文本来自一个 excel .csv 文件，因此有数百行七列宽的数据。此文件中的一行示例如下：

2012-10-01,759.05,765,756.21,761.78,3168000,761.78

我想按第一列中的日期搜索数百行。一旦我找到正确的行，我想提取逗号分隔字符串的第一个位置的数字，所以在这种情况下，我想提取数字 759.05 并将其分配给变量“Open”。

到目前为止，我的代码是：

strURL = "http://ichart.yahoo.com/table.csv?s=" & tickerValue
strBuffer = RequestWebData(strURL)

Dim Year As String = 2012
Dim Quarter As String = Q4
If Quarter = "Q4" Then
    Dim Open As Integer =
End If

一旦我可以将其缩小到正确的行，我认为类似 row.Split(",")(1).Trim) 的东西可能会起作用。

我已经做了很多研究，但我自己无法解决这个问题。有什么建议么！？！

附加信息：

Private Function RequestWebData(ByVal pstrURL As String) As String
    Dim objWReq As WebRequest
    Dim objWResp As WebResponse
    Dim strBuffer As String
    'Contact the website
    objWReq = HttpWebRequest.Create(pstrURL)
    objWResp = objWReq.GetResponse()
    'Read the answer from the Web site and store it into a stream
    Dim objSR As StreamReader
    objSR = New StreamReader(objWResp.GetResponseStream)
    strBuffer = objSR.ReadToEnd
    objSR.Close()

    objWResp.Close()

    Return strBuffer
End Function

更多附加信息：

我的代码的更完整的图片

Dim tickerArray() As String = {"GOOG", "V", "AAPL", "BBBY", "AMZN"}

For Each tickerValue In Form1.tickerArray

        Dim strURL As String
        Dim strBuffer As String
        'Creates the request URL for Yahoo
        strURL = "http://ichart.yahoo.com/table.csv?s=" & tickerValue

        strBuffer = RequestWebData(strURL)

        'Create Array
        Dim lines As Array = strBuffer.Split(New String() {Environment.NewLine}, StringSplitOptions.None)

        'Add Rows to DataTable
        dr = dt.NewRow()
        dr("Ticker") = tickerValue
        For Each columnQuarter As DataColumn In dt.Columns
            Dim s As String = columnQuarter.ColumnName
            If s.Contains("-") Then
                Dim words As String() = s.Split("-")
                Dim Year As String = words(0)
                Dim Quarter As String = words(1)
                Dim MyValue As String
                Dim Open As Integer
                If Quarter = "Q1" Then MyValue = Year & "-01-01"
                If Quarter = "Q2" Then MyValue = Year & "-04-01"
                If Quarter = "Q3" Then MyValue = Year & "-07-01"
                If Quarter = "Q4" Then MyValue = Year & "-10-01"
                For Each line In lines
                    Debug.WriteLine(line)
                    If line.Split(",")(0).Trim = MyValue Then Open = line.Split(",")(1).Trim
                    dr(columnQuarter) = Open
                Next
            End If

        Next
        dt.Rows.Add(dr)
    Next

现在在For Each line in lines循环中，Debug.WriteLine(line)输出 2,131 行：

从

Date,Open,High,Low,Close,Volume,Adj Close
2013-02-05,761.13,771.11,759.47,765.74,1870700,765.74
2013-02-04,767.69,770.47,758.27,759.02,3040500,759.02
2013-02-01,758.20,776.60,758.10,775.60,3746100,775.60

一路...

2004-08-19,100.00,104.06,95.96,100.34,22351900,100.34

但是，我期望的是在循环Debug.WriteLine(line)中一次输出一行。For Each line in lines所以我希望第一个输出是Date,Open,High,Low,Close,Volume,Adj Close，下一个输出是2013-02-05,761.13,771.11,759.47,765.74,1870700,765.74. 我预计这会发生 2,131 次，直到最后一个输出是2004-08-19,100.00,104.06,95.96,100.34,22351900,100.34

4

3 回答 3

4

您可以遍历这些行并调用String.Split以解析每行中的列，例如：

Dim lines() As String = strBuffer.Split(New String() {Environment.NewLine}, StringSplitOptions.None)
For Each line As String In lines
    Dim columns() As String = line.Split(","c)
    Dim Year As String = columns(0)
    Dim Quarter As String = columns(1)
Next

但是，有时 CSV 并不是那么简单。例如，电子表格中的单元格可能包含逗号字符，在这种情况下，它将以 CSV 格式表示，如下所示：

example cell 1,"example, with comma",example cell 3

为确保您正确处理所有可能性，我建议使用TextFieldParser类。例如：

Using parser As New TextFieldParser(New StringReader(strBuffer))
    parser.TextFieldType = FieldType.Delimited
    parser.SetDelimiters(",")
    While Not parser.EndOfData
        Try
            Dim columns As String() = parser.ReadFields()
            Dim Year As String = columns(0)
            Dim Quarter As String = columns(1)
        Catch ex As MalformedLineException
            ' Handle the invalid formatting error
        End Try 
    End While 
End Using
于 2013-02-01T17:14:21.950 回答
1

您可以使用String.Split这个 linq 查询：

Dim Year As Int32 = 2012
Dim Month As Int32 = 10
Dim searchMonth = New Date(Year, Month, 1)
Dim lines = strBuffer.Split({Environment.NewLine}, StringSplitOptions.None)
Dim dt As Date
Dim open As Double
Dim opens = From line In lines
    Let tokens = line.Split({","c}, StringSplitOptions.RemoveEmptyEntries)
    Where Date.TryParse(tokens(0), dt) AndAlso dt.Date = searchMonth AndAlso Double.TryParse(tokens(1), open)
If opens.Any() Then
    open = Double.Parse(opens.First().tokens(1))
End If
于 2013-02-01T17:08:49.973 回答
1

我会将其分解为List(of string())- 每一行都是列表中的一个新条目。

然后遍历列表并查看 Value(0)。 If Value(0) = MyValue, then Open = Value(1)

于 2013-02-01T16:54:06.940 回答