实现一个C#动态编译系统[实体类代码生成器代码分析]

在"实体类代码生成器3"中,用户可以使用C#代码来动态生成一些参数,比如代码类名生成规则,表名生成规则,初始化规则等.而要调用这些代码显然需要对代码进行运行时动态编译,幸好C#有了"万能"的反射系统,可以让我们轻松动态编译代码并调用.

OK,现在详细了解下"实体类代码生成器"中的动态编译类,首先定义一个RunnerMethod对象,用来保存和方法有关的信息:

C#代码

using System;
using System.Collections.Generic;
using System.Text;
using System.Reflection;
using CodeFactory.Library.Language;
using CodeFactory.Library.Config;

namespace CodeFactory.Library.CodeRunner
{
    public class RunnerMethod
    {
        private MethodInfo method;
        private object runnerObject;

        public RunnerMethod()
        {
        }

        public MethodInfo Method
        {
            get { return this.method; }
            set { this.method = value; }
        }

        public object RunnerObject
        {
            get { return this.runnerObject; }
            set { this.runnerObject = value; }
        }

        public object Run(object[] paras)
        {
            return this.method.Invoke(this.runnerObject, paras);
        }
    }
}

 

然后实现Runner类:

 

C#代码

using System;
using System.Collections.Generic;
using System.Text;
using System.CodeDom;
using System.CodeDom.Compiler;
using System.Reflection;
using System.IO;
using CodeFactory.Library.Language;
using CodeFactory.Library.Config;

namespace CodeFactory.Library.CodeRunner
{
    public class Runner
    {
        private EncoderInfo coderInfo;
        private string codeText;

        public EncoderInfo CodeInfo
        {
            get { return this.coderInfo; }
            set { this.coderInfo = value; }
        }

        public string CodeText
        {
            get { return this.codeText; }
        }

        public Runner()
        {
            this.coderInfo = ConfigManager.Info.SysEncoder;
            this.codeText = string.Empty;
        }

        public Runner(EncoderInfo rcode)
        {
            this.coderInfo = rcode;
            this.codeText = string.Empty;
        }

        public object Run(string methodName, object[] paras)
        {
            RunnerMethod method = this.CreateMethod(methodName);
            return method.Run(paras);
        }

        public RunnerMethod CreateMethod(string methodName)
        {
            StreamReader sr = new StreamReader(ConfigManager.CurrentPath + "\\" + this.coderInfo.CodeFile);
            this.codeText = sr.ReadToEnd();
            sr.Close();
            CompilerParameters vCompilerParameters = new CompilerParameters();
            vCompilerParameters.GenerateExecutable = false;
            vCompilerParameters.GenerateInMemory = true;
            foreach (string s in this.coderInfo.AssemblieList)
            {
                vCompilerParameters.ReferencedAssemblies.Add(s);
            }
            CompilerResults vCompilerResults =
                CodeDomProvider.CreateProvider("CSharp").CompileAssemblyFromSource(vCompilerParameters, this.codeText);
            Assembly vAssembly = null;
            try
            {
                vAssembly = vCompilerResults.CompiledAssembly;
            }
            catch (Exception)
            {
                throw new Exception(LanguageManager.StringManager["Error_RunCode"]);
            }
            object vTemp = vAssembly.CreateInstance(this.coderInfo.ClassName);
            Type t = vTemp.GetType();
            MethodInfo method = vTemp.GetType().GetMethod(methodName);
            RunnerMethod m = new RunnerMethod();
            m.RunnerObject = vTemp;
            m.Method = method;
            return m;
        }
    }
}

 

该类关键是CreateMethod方法,它用来生成编译后的方法对象供程序调用.当然,代码还有一些优化的空间,不过对于本程序,已经完全足矣.