的TryParse一个双

Question

我有一个变量（ApplicationVersionInformationArray（0）），它保存以下值：“1.0.0.1”

什么是确定是否该值大于1.0

这里的最佳方式是我当前的代码（ApplicationVersionInformationNumber是Double类型）：

If Double.TryParse(ApplicationVersionInformationArray(0), ApplicationVersionInformationNumber) = False Then 
     Return False 
    Else 
     If ApplicationVersionInformationNumber < 1 Then Return False 
    End If 

UPDATE

我发现有一个版本类可以轻松地进行这种转换。

Answer 1

这是一个精简版本的类，我写了很长时间回来比较版本。

Public Class Version 
    Implements IEquatable(Of Version) 

    Private _mmajorVersion As Integer = 0 
    Private _mminorVersion As Integer = 0 
    Private _mrivision As Integer = 0 
    Private _mbuild As Integer = 0 

    Sub New() 
     _mmajorVersion = 0 
     _mminorVersion = 0 
     _mrivision = 0 
     _mbuild = 0 
    End Sub 
    Sub New(ByVal VersionObj As Object) 
     If VersionObj Is DBNull.Value Then 
      _mmajorVersion = 0 
      _mminorVersion = 0 
      _mrivision = 0 
      _mbuild = 0 
     Else 
      ParseVersionString(VersionObj.ToString) 
     End If 
    End Sub 

    Public Sub New(ByVal VersionString As String) 
     ParseVersionString(VersionString) 
    End Sub 

    Public Property MajorVersion As Integer 
     Get 
      Return _mmajorVersion 
     End Get 
     Set(ByVal value As Integer) 
      _mmajorVersion = value 
     End Set 
    End Property 
    Public Property MinorVersion As Integer 
     Get 
      Return _mminorVersion 
     End Get 
     Set(ByVal value As Integer) 
      _mminorVersion = value 
     End Set 
    End Property 
    Public Property Revision As Integer 
     Get 
      Return _mrivision 
     End Get 
     Set(ByVal value As Integer) 
      _mrivision = value 
     End Set 
    End Property 

    Private Sub ParseVersionString(ByVal Version_String As String) 
     Dim p() As String = Version_String.Split(New Char() {"."}, 4) 
     If IsNumeric(p(0)) Then 
      _mmajorVersion = CInt(p(0)) 
     End If 
     If p.Length > 1 Then 
      If IsNumeric(p(1)) Then 
       _mminorVersion = CInt(p(1)) 
      End If 
     End If 
     If p.Length > 2 Then 
      If IsNumeric(p(2)) Then 
       _mrivision = CInt(p(2)) 
      End If 
     End If 
     If p.Length > 3 Then 
      If IsNumeric(p(3)) Then 
       _mbuild = CInt(p(3)) 
      End If 
     End If 
    End Sub 

    Public Shared Operator <(ByVal Version1 As Version, ByVal Version2 As Version) As Boolean 
     If Version1 = Version2 Then Return False 
     If Version1._mmajorVersion < Version2._mmajorVersion Then Return True 
     If Version1._mmajorVersion > Version2._mmajorVersion Then Return False 
     If Version1._mminorVersion < Version2._mminorVersion Then Return True 
     If Version1._mminorVersion > Version2._mminorVersion Then Return False 
     If Version1._mrivision < Version2._mrivision Then Return True 
     If Version1._mrivision > Version2._mrivision Then Return False 
     If Version1._mbuild < Version2._mbuild Then Return True 
     If Version1._mbuild > Version2._mbuild Then Return False 
     Return False 
    End Operator 
    Public Shared Operator >(ByVal Version1 As Version, ByVal Version2 As Version) As Boolean 
     Return Not (Version1 < Version2 Or Version1 = Version2) 
    End Operator 

    Public Shared Operator <=(ByVal Version1 As Version, ByVal Version2 As Version) As Boolean 
     If Version1 > Version2 Then Return False 
     Return True 
    End Operator 
    Public Shared Operator >=(ByVal Version1 As Version, ByVal Version2 As Version) As Boolean 
     If Version1 < Version2 Then Return False 
     Return True 
    End Operator 

    Public Shared Operator =(ByVal Version1 As Version, ByVal Version2 As Version) As Boolean 
     If Version1._mmajorVersion = Version2._mmajorVersion And _ 
      Version1._mminorVersion = Version2._mminorVersion And _ 
      Version1._mrivision = Version2._mrivision And _ 
      Version1._mbuild = Version2._mbuild Then 
      Return True 
     End If 
     Return False 
    End Operator 
    Public Shared Operator <>(ByVal Version1 As Version, ByVal Version2 As Version) As Boolean 
     Return Not Version1 = Version2 
    End Operator 
    Public Overrides Function Equals(ByVal obj As Object) As Boolean 
     If obj Is Nothing Then Return False 
     If obj.GetType.Name <> Me.GetType.Name Then Return False 
     Dim v As Version = DirectCast(obj, Version) 
     Return Me = v 
    End Function 
    Public Overloads Function Equals(ByVal other As Version) As Boolean Implements System.IEquatable(Of Version).Equals 
     Return Me = other 
    End Function 

    Public Overrides Function ToString() As String 
     Return String.Format("{0}.{1}.{2}.{3}", _mmajorVersion.ToString, _mminorVersion.ToString, _mrivision.ToString, _mbuild.ToString) 
    End Function 

    Public Overrides Function GetHashCode() As Integer 
     Return Me.ToString.GetHashCode() 
    End Function 
End Class 

您可以像这样调用类。

Return New Version(ApplicationVersionInformationArray(0)) > New Version("1.0.0.0") 

Answer 2

我发现这个代码在另一个论坛

Dim versionText As String = "1.0.0.1" 
    Dim currentVersion As Version 

    If Version.TryParse(versionText, currentVersion) Then 
     Dim minVersion As New Version(1, 0) 
     If currentVersion > minVersion Then 
      MessageBox.Show("Current version is greater than minimum version.") 
     Else 
      MessageBox.Show("Current version is NOT greater than minimum version.") 
     End If 
    Else 
     MessageBox.Show("Current version is not valid.") 
    End If 

如果你做一些细微的变化也应该成为你的目的。 Version中的属性包含版本中的所有字段。

Version class