Files
2026-07-10 15:25:05 +08:00

108 lines
3.4 KiB
C#

using System;
using System.CodeDom.Compiler;
using System.Reflection;
using System.Windows.Forms;
using CommonLib;
using System.Data;
using Microsoft.CSharp;
using System.Text;
namespace Lskj.Common {
/**/
/// <summary>
/// 动态求值
/// </summary>
public class Evaluator {
/**/
/// <summary>
/// 计算结果,如果表达式出错则抛出异常
/// </summary>
/// <param name="statement">表达式,如"1+2+3+4"</param>
/// <returns>结果</returns>
public static object Eval(string statement)
{
object obj = string.Empty;
try
{
if ((!string.IsNullOrEmpty(statement)) && (statement.Substring(0, 1) == "@"))
{
DataTable dt = SqlHelper.ExecuteDataSet(statement.Substring(1)).Tables[0];
if (dt == null)
return 0;
if (dt.Rows.Count < 1)
return 0;
return dt.Rows[0][0];
}
if (string.IsNullOrEmpty(statement))
statement = "1==1";
JSCaller caller = new JSCaller();
obj = caller.Eval(statement);
//obj = _evaluatorType.InvokeMember(
// "Eval",
// BindingFlags.InvokeMethod,
// null,
// _evaluator,
// new object[] { statement }
// );
}
catch (Exception ex)
{
//MessageBox.Show("请仔细检查配置列条件[" + statement + "]" + ex.StackTrace + "\r\n" + ex.Message);
PubUtil.WriteLog("请仔细检查配置列条件[" + statement + "]" + ex.Message);
}
//if (string.IsNullOrEmpty(obj + ""))
// return true;
return obj;
}
/**/
/// <summary>
///
/// </summary>
static Evaluator() {
try
{
CodeDomProvider provider = CodeDomProvider.CreateProvider("JScript");
CompilerParameters options = new CompilerParameters
{
ReferencedAssemblies = {
"System.dll",
AppDomain.CurrentDomain.BaseDirectory + @"Microsoft.JScript.dll"
},
GenerateInMemory = false
};
CompilerResults results;
results = provider.CompileAssemblyFromSource(options, _jscriptSource);
Assembly assembly = results.CompiledAssembly;
_evaluatorType = assembly.GetType("Evaluator");
_evaluator = Activator.CreateInstance(_evaluatorType);
}
catch (Exception)
{
}
}
private static object _evaluator = null;
private static Type _evaluatorType = null;
/**/
/// <summary>
/// JScript代码
/// </summary>
private static readonly string _jscriptSource =
@"class Evaluator
{
public function Eval(expr : String) : String
{
return eval(expr);
}
}";
public static object Eval_Ex(string statement) {
return null;
}
}
}