使用DataTable.Compute方法可以简化有限（即简单）的数学表达式。显然，这并不健壮（功能受限），而且滥用DataTable来实现这一目的可能会让人感到hackish，但我认为我应该补充当前答案。
示例：
var result = new DataTable().Compute("3+(7/3.5)", null); // 5
这种方法无法使用“Sin（90）”。请参阅DataColumn.Expression Property page以获取支持的函数列表，特别是在“聚合”部分下。
使用System.CodeDom命名空间是一种选择。
一些有用的链接：
"编辑：为了回应您的评论，这里提供一种方法来演示使用其等效的 Math 类方法替换三角函数。
C#
string expression = "(Sin(0) + Cos(0)+Tan(0)) * 10";
string updatedExpression = Regex.Replace(expression, @"(?<func>Sin|Cos|Tan)\((?<arg>.*?)\)", match =>
match.Groups["func"].Value == "Sin" ? Math.Sin(Int32.Parse(match.Groups["arg"].Value)).ToString() :
match.Groups["func"].Value == "Cos" ? Math.Cos(Int32.Parse(match.Groups["arg"].Value)).ToString() :
Math.Tan(Int32.Parse(match.Groups["arg"].Value)).ToString()
);
var result = new DataTable().Compute(updatedExpression, null); // 10
VB.NET
Dim expression As String = "(Sin(0) + Cos(0)+Tan(0)) * 10"
Dim updatedExpression As String = Regex.Replace(expression, "(?<func>Sin|Cos|Tan)\((?<arg>.*?)\)", Function(match As Match) _
If(match.Groups("func").Value = "Sin", Math.Sin(Int32.Parse(match.Groups("arg").Value)).ToString(), _
If(match.Groups("func").Value = "Cos", Math.Cos(Int32.Parse(match.Groups("arg").Value)).ToString(), _
Math.Tan(Int32.Parse(match.Groups("arg").Value)).ToString())) _
)
Dim result = New DataTable().Compute(updatedExpression, Nothing)
这里有一种评估表达式的方法，我在其他任何地方都没有看到过：使用 WebBrowser 控件和 JavaScript 的 eval() 方法：
Option Strict On
Imports System.Security.Permissions
<PermissionSet(SecurityAction.Demand, Name:="FullTrust")> _
<System.Runtime.InteropServices.ComVisibleAttribute(True)>
Public Class Form1
Dim browser As New WebBrowser
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
browser.ObjectForScripting = Me
'browser.ScriptErrorsSuppressed = True
browser.DocumentText = "<script>function evalIt(x) { return eval(x); }</script>"
End Sub
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
Dim result = browser.Document.InvokeScript("evalIt", New String() {"3+4*5"})
If result IsNot Nothing Then
MessageBox.Show(result.ToString()) '23
End If
End Sub
End Class
虽然有点晚了，但这正是您想要的（请确保解析输入以确保其中没有类似于“something + vbcrlf + exec“format c：”'的语句）：
用法：
MessageBox.Show(COR.Tools.EvalProvider.Eval("return 8-3*2").ToString())
类：
'Imports Microsoft.VisualBasic
Imports System
Namespace COR.Tools
Public Class EvalProvider
Public Shared Function Eval(ByVal vbCode As String) As Object
Dim c As VBCodeProvider = New VBCodeProvider
Dim icc As System.CodeDom.Compiler.ICodeCompiler = c.CreateCompiler()
Dim cp As System.CodeDom.Compiler.CompilerParameters = New System.CodeDom.Compiler.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 System.Text.StringBuilder = New System.Text.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("Imports Microsoft.VisualBasic" & vbCrLf)
sb.Append("Namespace MyEvalNamespace " & vbCrLf)
sb.Append("Class MyEvalClass " & 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 System.CodeDom.Compiler.CompilerResults = icc.CompileAssemblyFromSource(cp, sb.ToString())
Dim a As System.Reflection.Assembly = cr.CompiledAssembly
Dim o As Object
Dim mi As System.Reflection.MethodInfo
o = a.CreateInstance("MyEvalNamespace.MyEvalClass")
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 ' EvalProvider
End Namespace
我不知道VB.net是否内置了此功能，但我们通过链接IronPython运行时并传递表达式来实现这样的操作。这比使用反射要快得多。