using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Microsoft.CSharp;
using System.CodeDom.Compiler;
using System.Reflection;

namespace Bowin.Common.DynamicRun
{
    public class CodeDomHelper
    {
        #region 执行静态代码
        /// <summary>
        /// 执行代码，返回结果(默认引用了System.dll、System.Data.dll、System.Xml.dll、System.Web.dll 4个程序集)
        /// </summary>
        /// <param name="code">代码</param>
        /// <param name="arrReferencedAssemblies">要引用的程序集</param>
        /// <returns></returns>
        public static object ExecuteCode(string code, string[] arrReferencedAssemblies)
        {
            CSharpCodeProvider objCSharpCodePrivoder = new CSharpCodeProvider();
            CompilerParameters objCompilerParameters = new CompilerParameters();
            
            objCompilerParameters.ReferencedAssemblies.Add("System.dll"); 
            //引用dll
            objCompilerParameters.ReferencedAssemblies.Add("System.Data.dll");
            //引用dll
            objCompilerParameters.ReferencedAssemblies.Add("System.Xml.dll");
            //引用dll
            objCompilerParameters.ReferencedAssemblies.Add("System.Web.dll");
            //引用dll
            if (arrReferencedAssemblies != null)
                foreach (string item in arrReferencedAssemblies)
                    objCompilerParameters.ReferencedAssemblies.Add(item);
            objCompilerParameters.GenerateExecutable = false;
            objCompilerParameters.GenerateInMemory = true;

            
            CompilerResults cr = (objCSharpCodePrivoder.CompileAssemblyFromSource(objCompilerParameters,
                new [] { GenerateCode(code) }));
            
            if (cr.Errors.HasErrors)
            {
                StringBuilder l_err = new StringBuilder("编译错误：");
                foreach (CompilerError err in cr.Errors)
                {
                    l_err.AppendLine(err.ErrorText);
                }
                return l_err.ToString();
            }
            // 通过反射，调用HelloWorld的实例
            Assembly objAssembly = cr.CompiledAssembly;
            object objHelloWorld = objAssembly.CreateInstance("Bowin.Common.CommonOtherDynamicCodeGenerateClass");
            MethodInfo objMI = objHelloWorld.GetType().GetMethod("OutPut");
            // 调用执行
            return objMI.Invoke(objHelloWorld, null);
        }
        
        /// <summary>
        /// 执行代码，返回结果(默认引用了System.dll、System.Data.dll、System.Xml.dll 3个程序集)
        /// </summary>
        /// <param name="code"></param>
        /// <returns></returns>
        public static object ExecuteCode(string code)
        {
            return ExecuteCode(code, null);
        }
        
        private static string GenerateCode(string code)
        {
            StringBuilder sb = new StringBuilder();
            sb.Append("using System;");
            sb.Append(Environment.NewLine);
            sb.Append("using System.Text;");
            sb.Append(Environment.NewLine);
            sb.Append("using System.IO;");
            sb.Append(Environment.NewLine);
            sb.Append("using System.Data;");
            sb.Append(Environment.NewLine);
            sb.Append("using System.Xml;");
            sb.Append(Environment.NewLine);
            sb.Append("using System.Web;");
            sb.Append(Environment.NewLine);
            sb.Append("using System.Collections;");
            sb.Append(Environment.NewLine);
            sb.Append("using System.Collections.Generic;");
            sb.Append(Environment.NewLine);
            sb.Append("namespace Bowin.Common");
            sb.Append(Environment.NewLine);
            sb.Append("{");
            sb.Append(Environment.NewLine);
            sb.Append(" public class CommonOtherDynamicCodeGenerateClass");
            sb.Append(Environment.NewLine);
            sb.Append(" {");
            sb.Append(Environment.NewLine);
            sb.Append(" public object OutPut()");
            sb.Append(Environment.NewLine);
            sb.Append(" {");
            sb.Append(Environment.NewLine);
            sb.Append(" return " + code + ";");
            sb.Append(Environment.NewLine);
            sb.Append(" }");
            sb.Append(Environment.NewLine);
            sb.Append(" }");
            sb.Append(Environment.NewLine);
            sb.Append("}");
            return sb.ToString();
        }
        #endregion
    }
}