End reversible block

Command group	Flag affected	Reversible	Execute on client	Platform(s)
Constructs	NO	NO	NO	All

Syntax

Description

This command defines the end of a reversible block of commands. All reversible commands enclosed within the commands Begin reversible block/End reversible block are reversed when the method containing this block finishes. However, a reversible block in the $construct() method of a window class reverses when the window is closed and not when the method is terminated as is normally the case.

Example

# A method can contain more than one block of reversible commands. In this case,

# commands contained within all the blocks are reversed when the method terminates.

 
# All the commands in the following example are reversed when the method containing

# the block is finished

Begin reversible block
  
Disable menu line
 
mMyMenu/5

  
Set current list
 
iMyList

  
Build open window list
 (
Clear list
)

  
Calculate
 
iVar
 as 
0

  
Open window instance
 
wMyWindow

End reversible block

# When this block is reversed:

# The window instance wMyWindow is closed

# iVar returns to its former value

# iMyList is restored to its former contents and definition

# The current list is set to the former value

# Menu line 5 is enabled

 
# The following method hides fields Entry1 and Entry2 and installs the menu mCustomers

Begin reversible block
  
Hide fields
 
Entry1,Entry2

  
Install menu
 
mCustomers

End reversible block

OK message
 (
Icon
)
 {
MCUSTOMERS is now visible
}

# When this method ends, first MCUSTOMERS is removed, then the fields are shown.

 
# In the following example, the current list is iMyList

Begin reversible block
  
Set current list
 
iMyList2

  
Define list
 
fAccounts
.
Code
,
fAccounts
.
Surname
,
fAccounts
.
Balance

  
Set main file
 
fAccounts

  
# Build list  from select table

  
Enter data
End reversible block

# When this method terminates and the command block is reversed, the Main file is reset,

# the former list definition is restored and the current list is restored to iMyList.