Question

我正在使用Visual Basic 2010制作一个模拟停车的程序。当新车到达时，我将文本写入txt文件，格式如下：

＃

LicensePlate

全名

ArrivalDate

ArrivalTime

DepartDate

DepartTime

＃

继续使用上述格式。

如何通过输入他们的车牌让这个人找到该部分，然后它会显示该部分以便他们输入他们的离境详情？

谢谢！

Answer 1

不要在普通的TXT文件中写入数据。而是使用XML文件。您可以使用XML解析器来更快地获取。

Answer 2

这是一个答案。我用console作为样本。请参阅以下代码。

Imports System.Text
Imports System.IO

Module Module1

    Sub Main()
        Dim blnFound As Boolean = False

        Console.WriteLine("LicensePlate: ")
        Dim strLicensePlate As String = Console.ReadLine()

        Dim text As String = File.ReadAllText("TextData.txt")
        Dim index As Integer = text.IndexOf("" & strLicensePlate)
        If index >= 0 Then
            blnFound = True
        End If

        If blnFound = False Then
            Console.WriteLine("FullName: ")
            Dim strFullName As String = Console.ReadLine()
            Console.WriteLine("ArrivalDate: ")
            Dim strArrivalDate As String = Console.ReadLine()
            Console.WriteLine("ArrivalTime: ")
            Dim strArrivalTime As String = Console.ReadLine()

            Using w As StreamWriter = File.AppendText("TextData.txt")
                WriteData(strLicensePlate, strFullName, strArrivalDate, strArrivalTime, w)
            End Using
        Else
            Console.WriteLine("DepartureDate: ")
            Dim strDepartureDate As String = Console.ReadLine()
            Console.WriteLine("DepartureTime: ")
            Dim strDepartureTime As String = Console.ReadLine()


            Dim lines() As String = File.ReadAllLines("TextData.txt")
            For i As Integer = 0 To lines.Length - 1
                If lines(i).Contains(strLicensePlate) Then
                    lines(i + 4) = "DepartureDate:" & strDepartureDate
                    lines(i + 5) = "DepartureTime:" & strDepartureTime
                    File.WriteAllLines("TextData.txt", lines)
                    Exit For
                End If
            Next
            Display(strLicensePlate)
        End If

        Console.ReadKey()
    End Sub

    Private Sub WriteData(ByVal strLicensePlate As String, ByVal strFullName As String, ByVal strArrivalDate As String, _
                    ByVal strArrivalTime As String, ByVal w As TextWriter)
        w.WriteLine("#")
        w.WriteLine("LicensePlate: {0}", strLicensePlate)
        w.WriteLine("FullName: {0}", strFullName)
        w.WriteLine("ArrivalDate: {0}", strArrivalDate)
        w.WriteLine("ArrivalTime: {0}", strArrivalTime)
        w.WriteLine("DepartureDate:")
        w.WriteLine("DepartureTime:")
    End Sub

End Module

WriteData方法用于在汽车到达时写入数据。如您所见，DepartureDate和DepartureTime为空。获取text.IndexOf是要知道输入的LicensePlate是否已存在。如果它尚不存在，则索引返回-1。如果存在，则询问用户出发日期和时间。空白的出发日期和时间将替换为新输入的日期和时间。

File.ReadAllLines()逐行获取txt数据，并逐行搜索lines(indexNumber).Contains使用的关键字。如果lines(indexNumber).Contains返回true，则使用此代码开始用新输入的数据替换空的出发日期和时间，

lines(i + 4) = "DepartureDate:" & strDepartureDate
lines(i + 5) = "DepartureTime:" & strDepartureTime

还有4和5的索引号，因为索引当前指向LicensePlate的位置，而DepartureDate和DepartureTime是4和{分别位于5下方的{1}}行。

其他：

LicensePlate

上面的代码显示数据。只需将Private Sub Display(ByVal strLicensePlate As String) Dim lines() As String = File.ReadAllLines("TextData.txt") For i As Integer = 0 To lines.Length - 1 If lines(i).Contains(strLicensePlate) Then Console.WriteLine(lines(i + 1)) Console.WriteLine(lines(i + 2)) Console.WriteLine(lines(i + 3)) Console.WriteLine(lines(i + 4)) Console.WriteLine(lines(i + 5)) File.WriteAllLines("TextData.txt", lines) Exit For End If Next End Sub替换为您要将数据放置为Console.WriteLine或textbox的任何变量。并且不要忘记在label

之后在Display(strLicensePlate)部分内添加else

用VB编写后编辑TextFile

2 个答案: