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Once created, the .NET Component can be used the same way as any other Visual LANSA component. An instance of the component can be created and its properties, methods and events can be used. Some components are very simple and little programming is required to use them, others provide complex functionality and may require much more coding than using native Visual LANSA controls.

Define an instance of a component

Use the DEFINE_COM command. If the class does not have a constructor or has a constructor which takes no parameters then you may define the instance as either static or dynamic. Otherwise you must define the instance as dynamic:

     Define_Com Class

...

(#DOTNET1.TestClasses.MyClass)

...

 Name(#MyClass)

...

 Reference(*DYNAMIC)

...

If 
...
 the 
...
 class 
...
 is 
...
 a 
...
 control, 
...
 be 
...
 sure 
...
 to 
...
 parent 
...
 the 
...
 control 
...
 to 
...
 the 
...
 form 
...
 so 
...
 that 
...
 it 
...
 is 
...
 visible 
...
 on 
...
 the 
...
 form. 
...
 You 
...
 may 
...
 then 
...
 resize 
...
 and 
...
 move 
...
 the 
...
 control 
...
 in 
...
 Design 
...
 view:
...
     Define_
...
Com Class(#DOTNET1.DotNetControls.WebBrowserX)
...
 Name(#Browser)
...
 Displayposition(4)
...
 Parent(#COM_OWNER)
...
 Tabposition(4)
...
Instantiating 
...
 a 
...
 dynamic 
...
 instance
...
If 
...
 the 
...
 component 
...
 instance 
...
 has 
...
 been 
...
 defined 
...
 as 
...
 dynamic, 
...
 the 
...
 instance 
...
 will 
...
 need 
...
 to 
...
 be 
...
 instantiated 
...
 with 
...
 either 
...
 the 
...
 *New 
...
 or 
...
 SET_REF 
...
 commands. 
...
 Either 
...
 command 
...
 allows 
...
 you 
...
 to 
...
 specify 
...
 a 
...
 constructor.
...
How 
...
 to 
...
 define 
...
 classes 
...
 with 
...
 static 
...
 methods
...
To 
...
 use 
...
 static 
...
 methods 
...
 in 
...
 a 
...
 class 
...
 you 
...
 must 
...
 define 
...
 a 
...
 component 
...
 instance. 
...
 The 
...
 instance 
...
 may 
...
 be 
...
 defined 
...
 as 
...
 static 
...
 or 
...
 dynamic. 
...
 Once 
...
 defined, 
...
 static 
...
 methods 
...
 from 
...
 the 
...
 class 
...
 may 
...
 be 
...
 called 
...
 at 
...
 any 
...
 time. 
...
 If 
...
 a 
...
 dynamic 
...
 component 
...
 instance 
...
 has 
...
 been 
...
 defined, 
...
 static 
...
 methods 
...
 may 
...
 be 
...
 called 
...
 without 
...
 instantiating 
...
 the 
...
 instance. 
...
 This 
...
 allows 
...
 the 
...
 use 
...
 of 
...
 static 
...
 classes 
...
 and 
...
 also 
...
 allows 
...
 the 
...
 instantiation 
...
 of 
...
 classes 
...
 with 
...
 private 
...
 or 
...
 protected 
...
 constructors 
...
 (assuming 
...
 the 
...
 class 
...
 has 
...
 static 
...
 methods 
...
 to 
...
 instantiate 
...
 itself).
...
*NEW
...
If 
...
 the 
...
 class 
...
 does 
...
 not 
...
 have 
...
 a 
...
 constructor 
...
 or 
...
 has 
...
 a 
...
 constructor 
...
 that 
...
 takes 
...
 no 
...
 parameters, 
...
 then 
...
 you 
...
 may 
...
 specify 
...
 no 
...
 constructor 
...
 or 
...
 a 
...
 constructor 
...
 with 
...
 no 
...
 parameters. 
...
 Otherwise 
...
 the 
...
 parameters 
...
 should 
...
 be 
...
 passed 
...
 similar 
...
 to 
...
 a 
...
 method 
...
 call.
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Variable <= *New 

Variable <= *New 
 --- 
 Fully qualified class name 
Fully qualified class name ------------------ 
 >
>
>
>--------------------------------------------------------------------- 
 >
  |                                                             |
  -- .Constructor Name 
>
   |                                                                                                 |
    --.Constructor Name -------------------------------------------

                        |                                      |
                        -- ( 

                                       |                                                          |
                                       -- ( -------------------------------- 
 
 ) 
 -–
                              |                         |
                               
-–
                                               |                                         |
                                                -------- 
 Parameter 
Parameter -------- 

                                 |                   |
                                  

                                                    |                                |
                                                     ----------<---------- 

  

SET_REF
...
For 
...
 information, 
...
 refer 
...
 to 
...
the SET_REF in the Technical Reference Guide.
Example
     C#
        public ConstructorTests() {…}
        public ConstructorTests( int aNumber ) {…}
        public ConstructorTests( int aNumber, ref DateTime aDateTime, String aString ) {…}

     RDML
        Define_Com Class(#DOTNET1.TestClasses.ConstructorTests)
...
 Name(#LCom01)
...
 Reference(*DYNAMIC)
...


        Define Field(#LNum01)
...
 Type(*INT)
...
 Length(4)
...

        Define Field(#LStr01)
...
 Type(*CHAR)
...
 Length(50)
...

        Define Field(#LDTime01)
...
 Type(*DATETIME)
...
 Length(26)
...


        #LCom01 <= *New #DOTNET1.TestClasses.ConstructorTests
...

        Set_
...
Ref Com(#LCom01)
...
 To(*CREATE_
...
AS #DOTNET1.TestClasses.ConstructorTests)
...


        #LCom01 <= *New #DOTNET1.TestClasses.ConstructorTests.ConstructorTests()
...

        Set_
...
Ref Com(#LCom01)
...
 To(*CREATE_
...
AS #DOTNET1.TestClasses.ConstructorTests.ConstructorTests)
...


        #LCom01 <= *New #DOTNET1.TestClasses.ConstructorTests.ConstructorTests#2(
...
 #LNum01 #LDTime01 #LStr01 )
        Set_Ref Com(#LCom01)
...
 To(*CREATE_
...
AS #DOTNET1. TestClasses.ConstructorTests.ConstructorTests#2)
...
 Anumber(#LNum0501)
...
 Adatetime(#LDTi0501)
...
 Astring(#LStr0501)
...
Using 
...
 properties 
...
 and 
...
 variables
Syntax
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RDML Variable . .NET Property Name 

Syntax
RDML Variable . .NET Property Name 
 ----------------------------------------------- 
 >
                                    |                                           |
                                     -- \[ 
>
                                                             |                                                               |
                                                             -- \[ --------------------------------- 
 
 \] 
 -–
                                           |                             |
                                           
-–
                                                                      |                                           |
                                                                       ----------- 
 Index 
Index -----------

                                              |                       |
                                               

                                                                           |                                  |
                                                                            -----------<-----------

 
RDML Variable . .NET Variable Name
 
Example
C#
   public int Counter
   \{
      get \{ return mCount; \}
      set \{ mCount = value; \}
   \}
 
RDML
   Define_Com Class

RDML Variable . .NET Variable Name  
Example
     C#
        public int Counter    
        {
           get { return mCount; }
           set { mCount = value; }
        }

     RDML
        Define_Com Class(#DOTNET1.TestClasses.MyClass)
...
 Name(#NumericClass)
...


        #NumericClass.
...
Counter :=
...
 120

        #STD_
...
INT :=
...
 #NumericClass.Counter
...


        Begin_
...
Loop Using(#STD_INT)
...
 To(#NumericClass.Counter)
...
 Step(2)
...

        …
        End_Loop
...
Calling 
...
 Methods
Syntax
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RDML Variable . Method Name 

Syntax
RDML Variable . Method Name 
 ----------------------------------------------- 
 >
                             |                                           |
                              -- ( 
>
                                                   |                                                              |
                                                    -- ( --------------------------------- 
 
 ) 
 -–
                                    |                             |
                                     
-–
                                                           |                                           |
                                                           -------- 
 Parameter 
Parameter ----------

                                       |                       |
                                        

                                                              |                                    |
                                                                -----------<-----------

Example
C#
   public void
      IncrementDateByDays(
         ref DateTime                           dateTime,
         int                                    dayAdjustment )
   \{
      dateTime = dateTime.AddDays( dayAdjustment );
   \}
 
RDML
   Define_Com Class
Example
     C#
        public void
        IncrementDateByDays(
           ref DateTime                           dateTime,
           int                                    dayAdjustment )
        {
           dateTime = dateTime.AddDays( dayAdjustment );
        }
     RDML
        Define_Com Class(#DOTNET1.TestClasses.MyClass)
...
 Name(#LClass01)
...

        Define Field(#LDat01)
...
 Type(*DATETIME)
...

        Define Field(#LDat02)
...
 Type(*DATETIME)
...


        #LDat01 :=
...
 '1954-04-
...
25 10:04:00.000000'
...

        #LDat02 :=
...
 '1954-05-
...
05 10:04:00.000000'
...


        #LClass01.IncrementDateByDays(
...
 #LDat01 10 )

        If ((#LDat01 = #LDat02))
     …
        Endif


     C#
        public String
            DoubleIntegerReturnString(
              int                                    number,
              out int                                result )
        {
            result = number * 2;
            return String.Format( "Double {0} is {1}", number, result );
        }

     RDML
        Define_Com Class(#DOTNET1.TestClasses.MyClass)
...
 Name(#LClass01)
...

        Define Field(#LNum01)
...
 Type(*INT)
...
 Length(4)
...

        Define Field(#LNum02)
...
 Type(*INT)
...
 Length(4)
...

        Define Field(#LStr01)
...
 Type(*CHAR)
...
 Length(80)

        #LNum01 := 411
        #LStr01 := #LClass4101.DoubleIntegerReturnString( #LNum01 #LNum02 )
        If (#LNum02 = (#LNum01 * 2))
        …
        Endif
Event Handling
Event handling functions are defined using the EVTROUTINE command. See the EVTROUTINE documentation in the Technical Reference Guide for further details about this command. The basic syntax of the command is as follows:
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EVTROUTINE --- HANDLING ( Variable Name . Event Name 

 
   #LNum01 := 411
   #LStr01 := #LClass4101.DoubleIntegerReturnString( #LNum01 #LNum02 )
   If (#LNum02 = (#LNum01 * 2))
   …
   Endif
 
Event Handling
Event handling functions are defined using the EVTROUTINE command. See the [<span style="color: #0000ee"><span style="text-decoration: underline; ">EVTROUTINE</span></span>|../../../lansa015/Content/lansa/evtroutine.htm] documentation in the Technical Reference Guide for further details about this command. The basic syntax of the command is as follows:
EVTROUTINE --- HANDLING ( Variable Name . Event Name 
 )------------ 
 >
>
>
>---------------------------------------------------------------------------- 
 >
                 |                                              |
                  
>
                               |                                                                             |
                                 ---- 
 Parameter Name
Parameter Name( 
 Variable Name 
Variable Name ) 
 
 ---- 
 
 ) 
 
 -–

                   |                                     |
                    

                                    |                                                            |
                                      ---------------------<-----------------

Example
C#
   public class EventArgs1
   \{
      private String         mName;
 
      public EventArgs1() \{   \}
 
      public String Name
      \{
         get \{ return mName; \}
         set \{ mName = value; \}
      \}
   \}
 
   Public class EventTests
   \{
      public event MyEventDelegate MyEvent;
      public delegate void MyEventDelegate( String str, EventArgs1 eventArgs );
   \}
 
RDML
   Define_Com Class
Example
     C#
        public class EventArgs1    
        {
           private String         mName;
  
           public EventArgs1() {   }
  
           public String Name

        {
            get { return mName; }
            set \{ mName = value; }
         }
        }

        Public class EventTests
        {
           public event MyEventDelegate MyEvent;
           public delegate void MyEventDelegate( String str, EventArgs1 eventArgs );
        }

   RDML
      Define_Com Class(#DOTNET1.TestClasses.EventTests)
...
 Name(#EventTest)
...


      Evtroutine Handling(#EventTest.MyEvent)
...
 Str(#s1)
...
 EventArgs(#c1)
...

         #STD_
...
TEXT :=
...
 #s1
         #STD_NAME := #c1.Name
      Endroutine