Hi I am working on a project in which my class must execute the VB code provided by the user to make it simple. I am trying to recreate my own eval function. I am using the following code that I found on the Internet to complete this task.
Imports Microsoft.VisualBasic
Imports System
Imports System.Text
Imports System.CodeDom.Compiler
Imports System.Reflection
Imports System.IO
Namespace PAB.Util
Public Class EvalProvider
Public Function VS_Eval(ByVal vbCode As String) As Object
Dim c As VBCodeProvider = New VBCodeProvider
Dim icc As ICodeCompiler = c.CreateCompiler()
Dim cp As CompilerParameters = New CompilerParameters
cp.ReferencedAssemblies.Add("system.dll")
cp.ReferencedAssemblies.Add("system.xml.dll")
cp.ReferencedAssemblies.Add("system.data.dll")
' Sample code for adding your own referenced assemblies
'cp.ReferencedAssemblies.Add("c:\yourProjectDir\bin\YourBaseClass.dll")
'cp.ReferencedAssemblies.Add("YourBaseclass.dll")
cp.CompilerOptions = "/t:library"
cp.GenerateInMemory = True
Dim sb As StringBuilder = New StringBuilder("")
sb.Append("Imports System" & vbCrLf)
sb.Append("Imports System.Xml" & vbCrLf)
sb.Append("Imports System.Data" & vbCrLf)
sb.Append("Imports System.Data.SqlClient" & vbCrLf)
sb.Append("Namespace PAB " & vbCrLf)
sb.Append("Class PABLib " & vbCrLf)
sb.Append("public function EvalCode() as Object " & vbCrLf)
'sb.Append("YourNamespace.YourBaseClass thisObject = New YourNamespace.YourBaseClass()")
sb.Append(vbCode & vbCrLf)
sb.Append("End Function " & vbCrLf)
sb.Append("End Class " & vbCrLf)
sb.Append("End Namespace" & vbCrLf)
Debug.WriteLine(sb.ToString()) ' look at this to debug your eval string
Dim cr As CompilerResults = icc.CompileAssemblyFromSource(cp, sb.ToString())
Dim a As System.Reflection.Assembly = cr.CompiledAssembly
Dim o As Object
Dim mi As MethodInfo
o = a.CreateInstance("PAB.PABLib")
Dim t As Type = o.GetType()
mi = t.GetMethod("EvalCode")
Dim s As Object
s = mi.Invoke(o, Nothing)
Return s
End Function
End Class
End Namespace
The problem with the code is that it cannot access any variables or values there, so I decided to get the names of the variables, there the type values and the types there dynamically and recreate them in a class that is created dynamically.
, , , , , , , , , , .
, asp.net _load, , , vbCode, .
- , ,