Locate an assembly, determine types, and create an object using reflection : Reflection Assembly « Development Class « C# / C Sharp






Locate an assembly, determine types, and create an object using reflection

/*
C#: The Complete Reference 
by Herbert Schildt 

Publisher: Osborne/McGraw-Hill (March 8, 2002)
ISBN: 0072134852
*/


/* Locate an assembly, determine types, and create  
   an object using reflection. */ 
 
using System; 
using System.Reflection; 
 
public class ReflectAssemblyDemo { 
  public static void Main() { 
    int val; 
 
    // Load the MyClasses.exe assembly. 
    Assembly asm = Assembly.LoadFrom("MyClasses.exe"); 
 
    // Discover what types MyClasses.exe contains. 
    Type[] alltypes = asm.GetTypes(); 
    foreach(Type temp in alltypes) 
      Console.WriteLine("Found: " + temp.Name); 
 
    Console.WriteLine(); 
 
    // Use the first type, which is MyClass in this case. 
    Type t = alltypes[0]; // use first class found 
    Console.WriteLine("Using: " + t.Name); 
 
    // Obtain constructor info. 
    ConstructorInfo[] ci = t.GetConstructors(); 
 
    Console.WriteLine("Available constructors: "); 
    foreach(ConstructorInfo c in ci) { 
      // Display return type and name. 
      Console.Write("   " + t.Name + "("); 
 
      // Display parameters. 
      ParameterInfo[] pi = c.GetParameters(); 
 
      for(int i=0; i < pi.Length; i++) { 
        Console.Write(pi[i].ParameterType.Name + 
                      " " + pi[i].Name); 
        if(i+1 < pi.Length) Console.Write(", "); 
      } 
 
      Console.WriteLine(")"); 
    } 
    Console.WriteLine(); 
 
    // Find matching constructor. 
    int x; 
 
    for(x=0; x < ci.Length; x++) { 
      ParameterInfo[] pi =  ci[x].GetParameters(); 
      if(pi.Length == 2) break; 
    } 
 
    if(x == ci.Length) { 
      Console.WriteLine("No matching constructor found."); 
      return; 
    } 
    else 
      Console.WriteLine("Two-parameter constructor found.\n"); 
 
    // Construct the object.   
    object[] consargs = new object[2]; 
    consargs[0] = 10; 
    consargs[1] = 20; 
    object reflectOb = ci[x].Invoke(consargs); 
 
    Console.WriteLine("\nInvoking methods on reflectOb."); 
    Console.WriteLine(); 
    MethodInfo[] mi = t.GetMethods(); 
 
    // Invoke each method. 
    foreach(MethodInfo m in mi) { 
      // Get the parameters 
      ParameterInfo[] pi = m.GetParameters(); 
 
      if(m.Name.CompareTo("set")==0 && 
         pi[0].ParameterType == typeof(int)) { 
        // This is set(int, int). 
        object[] args = new object[2]; 
        args[0] = 9; 
        args[1] = 18; 
        m.Invoke(reflectOb, args); 
      } 
      else if(m.Name.CompareTo("set")==0 && 
         pi[0].ParameterType == typeof(double)) { 
        // This is set(double, double). 
        object[] args = new object[2]; 
        args[0] = 1.12; 
        args[1] = 23.4; 
        m.Invoke(reflectOb, args); 
      } 
      else if(m.Name.CompareTo("sum")==0) { 
        val = (int) m.Invoke(reflectOb, null); 
        Console.WriteLine("sum is " + val); 
      } 
      else if(m.Name.CompareTo("isBetween")==0) { 
        object[] args = new object[1]; 
        args[0] = 14; 
        if((bool) m.Invoke(reflectOb, args)) 
          Console.WriteLine("14 is between x and y"); 
      } 
      else if(m.Name.CompareTo("show")==0) { 
        m.Invoke(reflectOb, null); 
      } 
    } 
 
  } 
} 

//================================================================
/*
C#: The Complete Reference 
by Herbert Schildt 

Publisher: Osborne/McGraw-Hill (March 8, 2002)
ISBN: 0072134852
*/


// A file that contains three classes.  Call this file MyClasses.cs. 
 
using System; 
 
class MyClass { 
  int x; 
  int y; 
 
  public MyClass(int i) { 
    Console.WriteLine("Constructing MyClass(int). "); 
    x = y = i;  
    show(); 
  } 
 
  public MyClass(int i, int j) { 
    Console.WriteLine("Constructing MyClass(int, int). "); 
    x = i; 
    y = j; 
    show(); 
  } 
 
  public int sum() { 
    return x+y; 
  } 
 
  public bool isBetween(int i) { 
    if((x < i) && (i < y)) return true; 
    else return false; 
  } 
 
  public void set(int a, int b) { 
    Console.Write("Inside set(int, int). "); 
    x = a; 
    y = b; 
    show(); 
  } 
 
  // Overload set. 
  public void set(double a, double b) { 
    Console.Write("Inside set(double, double). "); 
    x = (int) a; 
    y = (int) b; 
    show(); 
  } 
 
  public void show() { 
    Console.WriteLine("Values are x: {0}, y: {1}", x, y); 
  } 
 
} 
 
class AnotherClass { 
  string remark; 
 
  public AnotherClass(string str) { 
    remark = str; 
  } 
 
  public void show() { 
    Console.WriteLine(remark); 
  } 
} 
 
public class Demo12 { 
  public static void Main() { 
    Console.WriteLine("This is a placeholder."); 
  } 
}





           
       








Related examples in the same category

1.Get Method ParamemtersGet Method Paramemters
2.Get type infomation: base type, is abstract, is com object, is sealed, is classGet type infomation: base type, is abstract, is com object, is sealed, is class
3.Get all methods from a classGet all methods from a class
4.Get all fields from a classGet all fields from a class
5.Get all properties from a classGet all properties from a class
6.Get all implemented interface from a classGet all implemented interface from a class
7.Using reflection to get information about an assembly
8.Demonstrate using Type class to discover information about a classDemonstrate using Type class to discover information about a class
9.Demonstrate dynamically invoking an object
10.Utilize MyClass without assuming any prior knowledge
11.Uses reflection to show the inherited members of a classUses reflection to show the inherited members of a class
12.Uses reflection to execute a class method indirectlyUses reflection to execute a class method indirectly
13.Deeper Reflection: Invoking Functions
14.Illustrates runtime type invocation
15.Illustrates unloading an application domain
16.Demonstrate typeofDemonstrate typeof
17.Create an object using reflectionCreate an object using reflection
18.Uses an object in another application domain
19.Illustrates creation of an application domainIllustrates creation of an application domain