关于公式解析的C#代码 比用反射更快 公式中去掉 Math

字符串中 Math 要大写,其余都要小写, 具体是JScript 的语法 , 遵循就是

//****************公式中去掉 Math

/// <summary>

/// 计算字符串表达式的通用类。

/// 引用Microsoft.JScript.Eval和Microsoft.JScript.Vsa.VsaEngine来实现公式计算方法

/// </summary>

/// <param name="strequation">字符串表达式</param>

/// <param name="paras">传入的参数</param>

/// <param name="paravalues">传入参数对应的值</param>

/// <param name="repara">返回的参数名</param>

/// <returns></returns>

public object RunFormula(string strequation, List<string> paras, List<string> paravalues, string repara)

{

StringBuilder myCode = new StringBuilder();

myCode.Append("function getValue() : double {");

for (int i = 0; i < paras.Count; i++)

{

myCode.Append("var " + paras[i] + " = " + paravalues[i] + " ;");

}

myCode.Append("var " + repara + "=0; with (Math){ ");

myCode.Append(repara + "=" + strequation + "};");

myCode.Append(" return " + repara + ";");

myCode.Append("}");

try

{

object ret = Microsoft.JScript.Eval.JScriptEvaluate(myCode + "getValue()",

Microsoft.JScript.Vsa.VsaEngine.CreateEngine());

return ret;

}

catch

{

return "false";

}

}