Art Of Creation - Dynamics AX Blog » CLR

Get folders and subfolders

Klaas Deforche — Fri, 08 Jan 2010 18:34:13 +0000

Someone on the Microsoft AX newsgroups asked how to get a list of directories and subdirectories given a folder. Here a job that does that:

static void KlForLoopFoldersSystemIO(Args _args)
{
int k; // counter for result loop
container dirs; // container for result
filePath path = @"C:\temp"; // input path

container getDirectories(str _dir, boolean _inclSubDirs = true)
{
container dList; // container to cast array into
int i; // counter for array loop
System.Array directories; // array for result from .NET call
#Define.Pattern("*") // input pattern: * = all
;

// assert interoppermissions for .NET interop
new InteropPermission(InteropKind::ClrInterop).assert();

// get directories using .NET interop
if(_inclSubDirs)
{
// include subdirectories
directories = System.IO.Directory::GetDirectories(_dir, #Pattern, System.IO.SearchOption::AllDirectories);
}
else
{
// only top directory
directories = System.IO.Directory::GetDirectories(_dir, #Pattern, System.IO.SearchOption::TopDirectoryOnly);
}

// loog .NET array and put the values in a container for easier use in x++
for( i=0;i<ClrInterop::getAnyTypeForObject(directories.get_Length()); i++ )
{
dList = conins(dList, conlen(dList)+1, ClrInterop::getAnyTypeForObject(directories.GetValue(i)));
}

// revert assertion to prevent multiple calls to the assert() method
CodeAccessPermission::revertAssert();

// return result container
return dList;
}
;

// get directories
dirs = getDirectories(path);

// use optional parameter to disable sub directories
// dirs = getDirectories(path, false);

// print the result
for(k=1;k<= conlen(dirs); k++)
{
// print the result to screen
info(conpeek(dirs, k));
}

// we're done
info("done");
}

Also check my post about how to loop files in a folder (method loopfilesSystemIO)

Append text from one file to an other

Klaas Deforche — Sat, 31 Oct 2009 07:28:24 +0000

This method will append all text from the original file to the destination file.
While this is a very easy task, the method shows many of the things you come across when you are working with files in AX, like:

- Using the #File macro
- Asserting FileIOPermission to be able to access files
- Asserting InteropPermission to be able to use .NET Interop
- Using a set to assert multiple permissions at once
- Using .NET Clr Interop in AX (better than winapi and winapiserver)
- Optional cleaning up after you’re done using reverAssert()

void AppendFileToFile(FileName original, FileName distination)
{
#File
FileIOPermission FileIOPermissionA = new FileIOPermission(distination, #io_append);
FileIOPermission FileIOPermissionR = new FileIOPermission(original, #io_read);
InteropPermission InteropPermission = new InteropPermission(InteropKind::ClrInterop);
Set permissionset = new set(types::Class);
;

// create permissionset
permissionset.add(FileIOPermissionA);
permissionset.add(FileIOPermissionR);
permissionset.add(InteropPermission);
// assert permissions
CodeAccessPermission::assertMultiple(permissionset);
// append text from source file to destination file
System.IO.File::AppendAllText(distination, System.IO.File::ReadAllText(original));

// limit the scope of the assert
CodeAccessPermission::revertAssert();
}

Because all permissions are taken care of, this code will run client side as well as server side.

Five nice-to-haves in Dynamics AX

Klaas Deforche — Tue, 20 Oct 2009 19:06:23 +0000

Here a some functionalities that I think are nice-to-haves in future versions of AX from a developer point of view. I hope they make sense :).

1. Select table where field in set
Consider a situation where you have a set or container filled with recId’s. When you want to loop all records that have one of these recId’s, it would be nice to be able to write something like this:

Set set = new Set(Types::Int64);
CustTable custTable;
;

set.add(5637166082);
set.add(5637166083);

while select custTable
where custTable.RecId IN set // this will not compile!
{
// do stuff
}

The only problem is that there is no ‘in’ operator in AX. You will either have to loop the set and select each record one at the time, or you’ll have to use the Query and QueryBuildRange classes to make this work.
The above example would be much nicer in my opinion.

2. Throwable exception classes
It would be nice to be able to create your own exceptions.
Java, for example, has Throwable and Exception classes that can be extended.
I won’t say that I completely understand these java classes (I’m not a Java guy), but I believe it would force developers to catch only exceptions they can handle, and not just all exceptions.
It would also make it possible to have more information as to why an exception has occoured when you catch it.

3. Try – catch – finally
This is a classic: the try-catch-finally is not supported in AX. When we look at C# for example, a try-catch can have a ‘finally’ block at the end. The code in this block is always executed, even if an exception occoured.

4. Events using CLR Interop
CLR Interop does not support event handling in AX. It would be nice to be able to assign an event handler to an event, so an event can trigger functionality in AX without complicated workarounds involving .NET wrapper classes, infinite loops, services or other creative solutions. (I’m thinking about things like FileSystemWatcher).

5. Code refactoring
When you rename an object in AX (Table, field, class, method, etc), there is no refactoring option. You have to manually rename all other instances of that object.
For example: it would be nice if, when you rename a field, AX had the option to automatically update all methods, forms, etc, where this field was used.