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日期:2018-08-15 点击:1801 来源:PB2.CN

反射类

using System; 
using System.Data; 
using System.Configuration; 
using System.Text; 
using System.CodeDom.Compiler; 
using Microsoft.CSharp; 
using System.Reflection; 
 
namespace Hot 

    /// <summary>    
    /// 本类用来将字符串转为可执行文本并执行    
    /// </summary>    
    public class HotUpdate 
    { 
        #region 构造函数 
 
        /// <summary>    
        /// 可执行串的构造函数    
        /// </summary>    
        /// <param name="items">    
        /// 可执行字符串数组    
        /// </param>    
        public MyEvaluator(EvaluatorItem[] items) 
        { 
            ConstructEvaluator(items);      //调用解析字符串构造函数进行解析    
        } 
 
        /// <summary>    
        /// 可执行串的构造函数    
        /// </summary>    
        /// <param name="returnType">返回值类型</param>    
        /// <param name="expression">执行表达式</param>    
        /// <param name="name">执行字符串名称</param>    
        public MyEvaluator(Type returnType, string expression, string name) 
        { 
            //创建可执行字符串数组    
            EvaluatorItem[] items = { new EvaluatorItem(returnType, expression, name) }; 
            ConstructEvaluator(items);      //调用解析字符串构造函数进行解析    
        } 
 
        /// <summary>    
        /// 可执行串的构造函数    
        /// </summary>    
        /// <param name="item">可执行字符串项</param>    
        public MyEvaluator(EvaluatorItem item) 
        { 
            EvaluatorItem[] items = { item };//将可执行字符串项转为可执行字符串项数组    
            ConstructEvaluator(items);      //调用解析字符串构造函数进行解析    
        } 
 
        /// <summary>    
        /// 解析字符串构造函数    
        /// </summary>    
        /// <param name="items">待解析字符串数组</param>    
        private void ConstructEvaluator(EvaluatorItem[] items) 
        { 
            //创建C#编译器实例 
            CodeDomProvider provider = CodeDomProvider.CreateProvider("C#"); 
             
            //过时了 
            //ICodeCompiler comp = provider.CreateCompiler(); 
             
            //编译器的传入参数    
            CompilerParameters cp = new CompilerParameters(); 
            cp.ReferencedAssemblies.Add("system.dll");              //添加程序集 system.dll 的引用    
            cp.ReferencedAssemblies.Add("system.data.dll");         //添加程序集 system.data.dll 的引用    
            cp.ReferencedAssemblies.Add("system.xml.dll");          //添加程序集 system.xml.dll 的引用    
            cp.GenerateExecutable = false;                          //不生成可执行文件    
            cp.GenerateInMemory = true;                             //在内存中运行    
 
            StringBuilder code = new StringBuilder();               //创建代码串    
            /*  
             *  添加常见且必须的引用字符串  
             */ 
            code.Append("using System; /n"); 
            code.Append("using System.Data; /n"); 
            code.Append("using System.Data.SqlClient; /n"); 
            code.Append("using System.Data.OleDb; /n"); 
            code.Append("using System.Xml; /n"); 
 
            code.Append("namespace SSEC.Math { /n");                  //生成代码的命名空间为EvalGuy,和本代码一样    
 
            code.Append("  public class _Evaluator { /n");          //产生 _Evaluator 类,所有可执行代码均在此类中运行    
            foreach (EvaluatorItem item in items)               //遍历每一个可执行字符串项    
            { 
                code.AppendFormat("    public {0} {1}() ",          //添加定义公共函数代码    
                                  item.ReturnType.Name,             //函数返回值为可执行字符串项中定义的返回值类型    
                                  item.Name);                       //函数名称为可执行字符串项中定义的执行字符串名称    
                code.Append("{ ");                                  //添加函数开始括号    
                code.AppendFormat("return ({0});", item.Expression);//添加函数体,返回可执行字符串项中定义的表达式的值    
                code.Append("}/n");                                 //添加函数结束括号    
            } 
            code.Append("} }");                                 //添加类结束和命名空间结束括号    
 
            //得到编译器实例的返回结果    
            CompilerResults cr = provider.CompileAssemblyFromSource(cp, code.ToString());//comp 
 
            if (cr.Errors.HasErrors)                            //如果有错误    
            { 
                StringBuilder error = new StringBuilder();          //创建错误信息字符串    
                error.Append("编译有错误的表达式: ");                //添加错误文本    
                foreach (CompilerError err in cr.Errors)            //遍历每一个出现的编译错误    
                { 
                    error.AppendFormat("{0}/n", err.ErrorText);     //添加进错误文本,每个错误后换行    
                } 
                throw new Exception("编译错误: " + error.ToString());//抛出异常    
            } 
            Assembly a = cr.CompiledAssembly;                       //获取编译器实例的程序集    
            _Compiled = a.CreateInstance("SSEC.Math._Evaluator");     //通过程序集查找并声明 SSEC.Math._Evaluator 的实例    
        } 
        #endregion 
 
        #region 公有成员 
        /// <summary>    
        /// 执行字符串并返回整型值    
        /// </summary>    
        /// <param name="name">执行字符串名称</param>    
        /// <returns>执行结果</returns>    
        public int EvaluateInt(string name) 
        { 
            return (int)Evaluate(name); 
        } 
        /// <summary>    
        /// 执行字符串并返回双精度值    
        /// </summary>    
        /// <param name="name">执行字符串名称</param>    
        /// <returns>执行结果</returns>    
        public double EvaluateDouble(string name) 
        { 
            return (double)Evaluate(name); 
        } 
        /// <summary>    
        /// 执行字符串并返回长整型数值    
        /// </summary>    
        /// <param name="name">执行字符串名称</param>    
        /// <returns>执行结果</returns>    
        public long EvaluateLong(string name) 
        { 
            return (long)Evaluate(name); 
        } 
        /// <summary>    
        /// 执行字符串并返回十进制数值    
        /// </summary>    
        /// <param name="name">执行字符串名称</param>    
        /// <returns>执行结果</returns>    
        public decimal EvaluateDecimal(string name) 
        { 
            return (decimal)Evaluate(name); 
        } 
        /// <summary>    
        /// 执行字符串并返回字符串型值    
        /// </summary>    
        /// <param name="name">执行字符串名称</param>    
        /// <returns>执行结果</returns>    
        public string EvaluateString(string name) 
        { 
            return (string)Evaluate(name); 
        } 
        /// <summary>    
        /// 执行字符串并返回布尔型值    
        /// </summary>    
        /// <param name="name">执行字符串名称</param>    
        /// <returns>执行结果</returns>    
        public bool EvaluateBool(string name) 
        { 
            return (bool)Evaluate(name); 
        } 
        /// <summary>    
        /// 执行字符串并返 object 型值    
        /// </summary>    
        /// <param name="name">执行字符串名称</param>    
        /// <returns>执行结果</returns>    
        public object Evaluate(string name) 
        { 
            MethodInfo mi = _Compiled.GetType().GetMethod(name);//获取 _Compiled 所属类型中名称为 name 的方法的引用    
            return mi.Invoke(_Compiled, null);                  //执行 mi 所引用的方法    
        } 
        #endregion 
 
        #region 静态成员 
        /// <summary>    
        /// 执行表达式并返回整型值    
        /// </summary>    
        /// <param name="code">要执行的表达式</param>    
        /// <returns>运算结果</returns>    
        static public int EvaluateToInteger(string code) 
        { 
            MyEvaluator eval = new MyEvaluator(typeof(int), code, staticMethodName);//生成 Evaluator 类的对像    
            return (int)eval.Evaluate(staticMethodName);                        //执行并返回整型数据    
        } 
        /// <summary>    
        /// 执行表达式并返回双精度值    
        /// </summary>    
        /// <param name="name">执行字符串名称</param>    
        /// <returns>执行结果</returns>    
        static public double EvaluateToDouble(string code) 
        { 
            MyEvaluator eval = new MyEvaluator(typeof(double), code, staticMethodName);//生成 Evaluator 类的对像    
            return (double)eval.Evaluate(staticMethodName);  
        } 
        /// <summary>    
        /// 执行表达式并返回长整型数值    
        /// </summary>    
        /// <param name="name">执行字符串名称</param>    
        /// <returns>执行结果</returns>    
        static public long EvaluateToLong(string code) 
        { 
            MyEvaluator eval = new MyEvaluator(typeof(long), code, staticMethodName);//生成 Evaluator 类的对像    
            return (long)eval.Evaluate(staticMethodName);  
        } 
        /// <summary>    
        /// 执行表达式并返回十进制数值    
        /// </summary>    
        /// <param name="name">执行字符串名称</param>    
        /// <returns>执行结果</returns>    
        static public decimal EvaluateToDecimal(string code) 
        { 
            MyEvaluator eval = new MyEvaluator(typeof(decimal), code, staticMethodName);//生成 Evaluator 类的对像    
            return (decimal)eval.Evaluate(staticMethodName);  
        } 
        /// <summary>    
        /// 执行表达式并返回字符串型值    
        /// </summary>    
        /// <param name="code">要执行的表达式</param>    
        /// <returns>运算结果</returns>    
        static public string EvaluateToString(string code) 
        { 
            MyEvaluator eval = new MyEvaluator(typeof(string), code, staticMethodName);//生成 Evaluator 类的对像    
            return (string)eval.Evaluate(staticMethodName);                     //执行并返回字符串型数据    
        } 
        /// <summary>    
        /// 执行表达式并返回布尔型值    
        /// </summary>    
        /// <param name="code">要执行的表达式</param>    
        /// <returns>运算结果</returns>    
        static public bool EvaluateToBool(string code) 
        { 
            MyEvaluator eval = new MyEvaluator(typeof(bool), code, staticMethodName);//生成 Evaluator 类的对像    
            return (bool)eval.Evaluate(staticMethodName);                       //执行并返回布尔型数据    
        } 
        /// <summary>    
        /// 执行表达式并返回 object 型值    
        /// </summary>    
        /// <param name="code">要执行的表达式</param>    
        /// <returns>运算结果</returns>    
        static public object EvaluateToObject(string code) 
        { 
            MyEvaluator eval = new MyEvaluator(typeof(object), code, staticMethodName);//生成 Evaluator 类的对像    
            return eval.Evaluate(staticMethodName);                             //执行并返回 object 型数据    
        } 
        #endregion 
 
        #region 私有成员 
        /// <summary>    
        /// 静态方法的执行字符串名称    
        /// </summary>    
        private const string staticMethodName = "__foo"; 
        /// <summary>    
        /// 用于动态引用生成的类,执行其内部包含的可执行字符串    
        /// </summary>    
        object _Compiled = null; 
        #endregion 
    } 
 
 
    /// <summary>    
    /// 可执行字符串项(即一条可执行字符串)    
    /// </summary>    
    public class EvaluatorItem 
    { 
        /// <summary>    
        /// 返回值类型    
        /// </summary>    
        public Type ReturnType; 
        /// <summary>    
        /// 执行表达式    
        /// </summary>    
        public string Expression; 
        /// <summary>    
        /// 执行字符串名称    
        /// </summary>    
        public string Name; 
        /// <summary>    
        /// 可执行字符串项构造函数    
        /// </summary>    
        /// <param name="returnType">返回值类型</param>    
        /// <param name="expression">执行表达式</param>    
        /// <param name="name">执行字符串名称</param>    
        public EvaluatorItem(Type returnType, string expression, string name) 
        { 
            ReturnType = returnType; 
            Expression = expression; 
            Name = name; 
        } 
    } 
}


测试类

class Test 
    { 
        /// <summary> 
        /// The main entry point for the application. 
        /// </summary> 
        [STAThread] 
        static void Main(string[] args) 
        { 
            Console.WriteLine("Test0: {0}", MyEvaluator.EvaluateToInteger("(30 + 4) * 2")); 
            Console.WriteLine("Test1: {0}", MyEvaluator.EvaluateToString("/"Hello /" + /"There/"")); 
            Console.WriteLine("Test2: {0}", MyEvaluator.EvaluateToBool("30 == 40")); 
            Console.WriteLine("Test3: {0}", MyEvaluator.EvaluateToObject("new DataSet()")); 
            Console.WriteLine("Test4: {0}", MyEvaluator.EvaluateToDouble("(12.4+2.2)*0.4")); 
            Console.WriteLine("Test5: {0}", MyEvaluator.EvaluateToLong("(12+1000)*1000")); 
            Console.WriteLine("Test6: {0}", MyEvaluator.EvaluateToString("/"double max==/"+double.MaxValue"));//decimal.MaxValue+/",/"+ 
             
 
            EvaluatorItem[] items = { 
                                    new EvaluatorItem(typeof(int), "(30 + 4) * 2", "GetNumber"), 
                                    new EvaluatorItem(typeof(string), "/"Hello /" + /"There/"", "GetString"), 
                                    new EvaluatorItem(typeof(bool), "30 == 40", "GetBool"), 
                                    new EvaluatorItem(typeof(object), "new DataSet()", "GetDataSet") 
                                    }; 
 
            MyEvaluator eval = new MyEvaluator(items); 
            Console.WriteLine("TestStatic0: {0}", eval.EvaluateInt("GetNumber")); 
            Console.WriteLine("TestStatic1: {0}", eval.EvaluateString("GetString")); 
            Console.WriteLine("TestStatic2: {0}", eval.EvaluateBool("GetBool")); 
            Console.WriteLine("TestStatic3: {0}", eval.Evaluate("GetDataSet")); 
            Console.ReadLine(); 
        } 
    }


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c#去除字符串中的空格,回车,换行符,制表符

c#去除字符串中的空格,回车,换行符,制表符

c#去除字符串中的空格,回车,换行符,制表符
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