C#基础_反射

Excell导入调用泛型方法实例总结：

学习：

public class ReflectMethodTest
{
    public ReflectMethodTest()
    {
        Console.WriteLine("this is ReflectMethod");
    }

    public string Show()
    {
        return "show 无参方法";
    }
    public string Show(string name)
    {
        return $"show 有参方法，参数为{name}";
    }

    public string Show(int count, string name)
    {
        return $"show 有参方法，
            参数为count:{count},name:{name}";
    }

    public string Show(string name, int count)
    {
        return $"show 有参方法，参数为count:{count},name:{name}";
    }
    public string SHHHH<T>(Student student) where T : Student
    {
        return $"调用泛型方法 {student.Name}";
    }
    public string SHHHH<T>(Student student,int count) where T : Student
    {
        return $"调用泛型方法 {student.Name},count {count}";
    }
    ///调用带泛型参数的重载的泛型方法
    public string Show<T>(T t)
    {
        return $"this is Show<T> method params[name:{t} ]";
    }
}

调用

static void Main(string[] args)
{
    System.Console.WriteLine("反射的学习--------------------------------");
    var object1 = new ReflectMethodTest();
    var type = typeof(ReflectMethodTest);
    var methods = type.GetMethods();
    foreach (var item in methods)
    {
        Console.WriteLine(item.Name);
    }

    System.Console.WriteLine("---调用无参方法--------------------------------");
    var show = type.GetMethod("Show", new Type[] { });
    var res = show.Invoke(object1, new object[] { });
    Console.WriteLine(res);
    System.Console.WriteLine("---调用一个参数的有参方法(string name)");
    var show1 = type.GetMethod("Show", new Type[] { typeof(string) });
    var res1 = show1.Invoke(object1, new object[] { "张三" });
    Console.WriteLine(res1);

    System.Console.WriteLine("---调用二个参数的有参方法(int count,string name)");
    var show2 = type.GetMethod("Show", new Type[] { typeof(int), typeof(string) });
    var res2 = show2.Invoke(object1, new object[] { 100, "张三" });
    Console.WriteLine(res2);

    System.Console.WriteLine("---调用二个参数的有参方法(string name,int count)");
    var show3 = type.GetMethod("Show", new Type[] { typeof(string), typeof(int) });
    var res3 = show3.Invoke(object1, new object[] { "李四", 10890 });
    Console.WriteLine(res3);


    System.Console.WriteLine("---调用泛型方法");
    MethodInfo mi = type.GetMethod("SHHHH", new Type[] { typeof(Student), typeof(int) });
    ///获取可使用的泛型方法，必须通过该方法才能传递泛型参数
    MethodInfo miConstructed = mi.MakeGenericMethod(new Type[] { typeof(int) });

    var res4 = miConstructed.Invoke(object1, new object[] { new Student() { Name = "ma6", Age = 28, ClassName = "4年纪" }, 1 });
    Console.WriteLine(res4);
    
    System.Console.WriteLine("---调用带泛型参数的重载的泛型方法");
    MethodInfo showMethodT = null;
    var methods = type.GetMethods();
    foreach (var method in methods)
    {
        if (method.ToString() == "System.String Show[T](T)")
        {
            showMethodT = method;
            var showMethodTCtor = showMethodT.MakeGenericMethod(typeof(string));
            var res1 = showMethodTCtor.Invoke(new ReflectMethodTest2(), new object[] { "李四" });
            Console.WriteLine(res1);
        }
    }

    Console.Read();
}

输出结果

--- 调用带泛型参数的重载的泛型方法

工作中的例子

/// <summary>
/// 得到程序集
/// </summary>
static Assembly GetAssembly()
{
    AssemblyName name = new AssemblyName("Henkel.DataModels");//我的程序集的名称为"CommonEntity"
    var result = Assembly.Load(name);
    //Console.WriteLine(result.FullName);
    return result;
    //TestGetIntance(result);
    //GetIntanceType(result);
}

/// <summary>
/// 获取实体类型
/// </summary>
/// <param name="assembly"></param>
public Type GetIntanceType(string str, Assembly assembly = null)
{
    if (assembly == null)
    {
        assembly=GetAssembly();
    }
    var clstype = assembly.GetType($"Henkel.DataModels.Entity.{str}");
    return clstype;
}

调用例子1

//var xxx= IDbMaintenance
//获取到接口类型
var sqlSugarClient = ExcelHelper.GetDb().DbMaintenance;
//ExcelHelper.GetDb().DbMaintenance.TruncateTable<T>();  
var temp = typeof(IDbMaintenance).GetMethod("TruncateTable", new Type[] { });
var methodInfo = temp.MakeGenericMethod(new ReflectHellp().GetIntanceType(tableName));
methodInfo.Invoke(sqlSugarClient, new object[] { });
CommonHelp.writeLine(string.Format("{0} 清除完毕   DateTime:{1}", tableName, DateTime.Now.ToLongTimeString()));

调用例子2（通过字符串调用泛型方法）

///通过字符串调用泛型方法
///ExcelHelper.WorkSheetImport<T>(package)
var methodInfo=typeof(ExcelHelper).GetMethod();
///如果对应的方法名有重载的，要把参数传递进来.(WorkSheetImport:方法名,)
var methodInfo = typeof(ExcelHelper).GetMethod("WorkSheetImport",
                                               new Type[] { package.GetType() }).MakeGenericMethod(new ReflectHellp().GetIntanceType(tableName));
var import = (int)methodInfo.Invoke(null, new object[] { package });