Using Reflections in C#
Tip
ekzemplyarini dnamik yaratishda, tipnig mavjud ob’yekt bilan aloqasini
ta’minlashda, mavjud ob’yektning tipini aniqlashda va uning metodlarini
ishlatishda(chaqirishda) yoki uning maydonlari va xususiyatlariga dostup
olishda Reflectiondan foydalaniladi.
Masalan,
string
myStringValue=”Learning reflections in C#”;
System.Type
type= myStringValue.GetType();
System.Console.WriteLine(type);
Natija:
Sytem.String
Ushbu
misolda GetType orqali reflection ishlatildi va ob’yektning tipi aniqlandi
Reflection –
shunday jarayonki unda dastur vaziyatga qarab o’z struktura va ko’rinishini o’zgartirishi
mumkin.
Question 1:
Dastur ishlayotgan vaqtda biror string tipidagi o’zgaruvchining faqat
nominigina bilgan holda uning qiymatini qanday o’zgartirish mumkin?
Answer:
class Program
{
private static string a="test1", b="test2", c="test3";
private static string s = "test string";
static void Main(string[] args)
{
Console.WriteLine("O'zgaruvchi
nomini kiriting:");
string varName = Console.ReadLine();
Console.WriteLine("O'zgaruvchi
yangi qiymatini kiriting:");
string newValue = Console.ReadLine();
Type t = typeof(Program);
FieldInfo fieldInfo=t.GetField(varName,BindingFlags.NonPublic|BindingFlags.Static);
if (fieldInfo != null)
{
string varInfo1 = string.Format("{0}
o'zgaruvchining joriy qimati:{1}",fieldInfo.Name,fieldInfo.GetValue(null));
Console.WriteLine(varInfo1);
fieldInfo.SetValue(null,newValue);
string varInfo2 = string.Format("{0}
o'zgaruvchining yangi qimati:{1}",
fieldInfo.Name, fieldInfo.GetValue(null));
Console.WriteLine(varInfo2);
}
else Console.WriteLine("Bunday
o'zgaruvchi aniqlanmagan!");
Console.ReadLine();
}
}
Joriy
koddagi assembly(project, ya'ni assemblyni build qilganda .exe yoki .dll fayl ko'rinishga o'tadi) tiplarni(projectdagi classlar, interfacelar,…) aniqlash
Projectda
quyidagilar aniqlangan bo’lsin:
namespace xyz.Test1.fullinfo
{
public class ClassTest
{
//…
}
}
namespace ReflactionTest
{
abstract class AbstractClassTest
{
//…
}
}
namespace ReflactionTest
{
interface Interface1
{
//…
}
}
Barcha assembly tiplar ro’yxatini
quyidagi kod yordamida aniqlash mumkin:
namespace ReflactionTest
{
class Program
{
static void Main(string[] args)
{
Assembly assembly = Assembly.GetExecutingAssembly();
Type[] assemblyTypes = assembly.GetTypes();
foreach (Type t in assemblyTypes)
Console.WriteLine(t.Name);
Console.ReadLine();
}
}
}
Natija:
ClassTest
ArstractClassTest
Interface1
Sinf nomi
orqali undagi metodni Reflection yordamida ishlatish:
using System;
using
System.Collections.Generic;
using System.Text;
using System.Reflection;
namespace ReflectionTest
{
class Program
{
static void Main(string[] args)
{
Type testType = typeof(TestClass);
ConstructorInfo
ctor = testType.GetConstructor(System.Type.EmptyTypes);
if(ctor != null)
{
object instance = ctor.Invoke(null);
MethodInfo
methodInfo = testType.GetMethod("TestMethod");
Console.WriteLine(methodInfo.Invoke(instance, new object[] { 20 }));
}
Console.ReadKey();
}
}
public class TestClass
{
private int testValue = 35;
public int TestMethod(int numberToAdd)
{
return this.testValue +
numberToAdd;
}
}
}
Question 2: Base Calss “bolalari”ni qanday aniqlash mumkin?
Answer 1:
Masalan, BaseClass nomi BasePerson b.sa:
var result = AppDomain.CurrentDomain.GetAssemblies()
.SelectMany(assembly
=> assembly.GetTypes())
.Where(type =>
type.IsSubclassOf(typeof(BasePerson)));
foreach (Type item in result)
{
var personObject = Activator.CreateInstance(item);
MethodInfo methodInfo = item.GetMethod("<Person sinfidagi metod nomi>");
//ParameterInfo[]
parameters = methodInfo.GetParameters();
object[] parameters = new object[] { parametr1,parametr2,…,parametrN };
var methodResult = methodInfo.Invoke(personObject,
parameters);
…
}
Answer
2:
BaseLogic
sinfi abstract shaklda aniqlangan va u check(column1,column2) metodiga ega,
undan inherities olgan barcha sinflardning check metodi natijalarini olish:
` var logicList = new List<BaseLogic>();
var types = Assembly.GetExecutingAssembly().GetTypes();
foreach (var type in types)
{
if (type.IsSubclassOf(typeof(BaseLogic)))
{
logicList.Add((BaseLogic)Activator.CreateInstance(type));
}
}
Ishlatishda:
logicList.Where(w=>w.Weight<=weight).ToList().ForEach(logic=>
{
primeryKeyColumn.Parent =
_tables.Find(f => f.ID == primeryKeyColumn.ParentID);
forignKeyColumn.Parent =
_tables.Find(f => f.ID == forignKeyColumn.ParentID);
var relationship =
logic.Check(primeryKeyColumn,forignKeyColumn);
}
Kabi
bo’ladi
Used LINKS:
