如何检测电脑是否安装了.net framework

[已关闭问题]

我的这个项目是用vs2005做的，程序启动的时候需要检测用户是否已经安装.net framework，在网络上查了一下，最广泛的是这样的代码

Code
Public Function DoesDotNETFrameworkExist(ByVal udeVersion As DotNETFrameworkVersions) As Boolean 

Dim o_blnRet As Boolean 
Dim o_strRet As String 

With New cRegistry 
.hKey = HKEY_LOCAL_MACHINE 
.KeyPath = "Software\Microsoft\.NETFramework" 
If .DoesKeyExist() Then 
.KeyPath = "Software\Microsoft\.NETFramework" 
o_strRet = GetRegValue(.GetRegistryValue("InstallRoot", "")) 
o_blnRet = (o_strRet <> "") 
If o_blnRet Then 
With New cFileFuncs 
Select Case udeVersion 
Case dnfvV1 
o_blnRet = .DoesFileExistEx(o_strRet & "v1.0.3705\mscorlib.dll") 
Case dnfvV1_1 
o_blnRet = .DoesFileExistEx(o_strRet & "v1.1.4322\mscorlib.dll") 
Case dnfvVAny 
o_blnRet = .DoesFileExistEx(o_strRet & "v1.0.3705\mscorlib.dll") 
If o_blnRet Then 
Else 
o_blnRet = .DoesFileExistEx(o_strRet & "v1.1.4322\mscorlib.dll") 
End If 
End Select 
End With 
Else 

End If 
Else 
o_blnRet = False 
End If 
End With 

DoesDotNETFrameworkExist = o_blnRet 

End Function