// 示例：strFormULA = (a+b)*c 

 // 如果替换a=1 b=1 c=2 则结果为 (1+1)*2 = 4

 public int CalculateStringFormula(string strFormULA )

{

    var type = Type.GetTypeFromProgID("MSScriptControl.ScriptControl");

    var obj = Activator.CreateInstance(type);

    type.InvokeMember("Language", System.Reflection.BindingFlags.SetProperty, null, obj, new object[] { "javascript" });

    int result = Convert.ToInt32(type.InvokeMember("Eval", System.Reflection.BindingFlags.InvokeMethod, null, obj, new object[] { strFormULA }));

    return result;

}