Category: programming

I haven’t posted any code on here in a while, so here’s a quick little bit of code that might be useful to somebody. I had to write some code this week to do conversion from base 10 to base 36 and back, in Dynamics AX. So I just took some simple code from the Wikipedia article on base 36 and converted it to X++. Nothing fancy. The code below is all in a job, but I’ll probably put it in a utility class when I actually implement it.

// https://gist.github.com/andyhuey/5c2404b65939b5fccab8
static void AjhBase36Test(Args _args)
{
    // ajh 2014-05-07: 611.23
    // adapted from http://en.wikipedia.org/wiki/Base_36.
    // note: handles non-negative integers only.
    #define.NBASE(36)
    #define.CLIST("0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ")

    int64 base36_decode(str base36_input)
    {
        int64 result = 0;
        real pow = 0;
        int i, pos;
        str c;

        for (i = strLen(base36_input); i > 0; i--)
        {
            c = subStr(base36_input, i, 1);
            pos = strScan(#CLIST, c, 1, #NBASE) - 1;
            if (pos == -1)
                return pos;  // error
            result += pos * power(#NBASE, pow);
            pow++;
        }
        return result;
    }
    str base36_encode(int64 input_num)
    {
        int64 work_num = input_num;
        str result = "";
        int digitidx;
        str c;

        do {
            digitidx = int642int(work_num mod #NBASE);
            c = subStr(#CLIST, digitidx + 1, 1);
            result += c;
            work_num = work_num div #NBASE;
        } while (work_num > 0);
        return strReverse(result);
    }

    print base36_decode("");
    print base36_decode("0");
    print base36_decode("A"); // 10
    print base36_decode("7PS"); // 10,000
    print base36_decode("255S"); // 100,000
    print base36_decode("!@#$"); // error
    print base36_encode(0);
    print base36_encode(123);
    print base36_encode(10000);
    print base36_encode(100000);
    pause;
}

It’s been a while since I’ve posted anything related to Dynamics AX / X++, so I thought I’d write up something I stumbled across recently. I had created a custom form, with a number of buttons on it. Two of the buttons needed to be available only to users in a certain role.

Well, first, I should point out that this can be done without any code. See here and here for information on that. And there are good reasons to do it this way, in many cases.

But there are also some good reasons to do this in code. It allows you to document what you’re doing and why, and it gives you more flexibility than just doing it through properties in the AOT. In my case, the business rules around this didn’t really fit into the permissions available in the AOT (Read, Update, Create, and Delete), so while I could have picked one of those and used it, it wouldn’t have accurately reflected the actual use case.

So I first wanted to find a method in X++ that would tell me if a given user was in a given role. I’m familiar with Roles.IsUserInRole from the .NET Framework, and have used it frequently in the context of ASP.NET sites using custom membership providers. So I looked for something similar in AX. That led me to the SysUserManagement Class.

I wound up writing a utility method that made use of this class:

// https://gist.github.com/andyhuey/9326912
/// <summary>
/// return true is the specified user is in any of the roles in the roleNames container.
/// </summary>
/// <param name="axUserId">
/// AX user id, e.g. curUserId()
/// </param>
/// <param name="roleNames">
/// container of role names to check. (use role NAME, not label.)
/// </param>
/// <returns>
/// true if user is in ANY of the specified roles.
/// </returns>
/// <remarks>
///
/// </remarks>

public static boolean isUserInRole(UserId axUserId, container roleNames)
{
    SysUserManagement userManagement = new SysUserManagement();
    List roleList = userManagement.getRolesForUser(axUserId);
    ListEnumerator listEnum = null;
    boolean isInRole = false;
    str roleStr = '';

    if (!roleList)
        return false;

    listEnum = roleList.getEnumerator();
    while (listEnum.moveNext())
    {
        if (conFind(roleNames, listEnum.current()))
            return true;
    }

    return false;
}

It worked fine on my VM, when logged in under my own ID. But, after deployment, it quickly became apparent that X++ code running under a normal user account (without SYSADMIN rights) can’t call methods in the SysUserManagement class. Now, there’s nothing I can see in the documentation that indicates that, but I should of course have tested my code under a normal user account.

So I rewrote my code to access the appropriate role-related tables directly, and it turns out that a normal user can do that, no problem:

// https://gist.github.com/andyhuey/9326939
/// <summary>
/// return true is the specified user is in any of the roles in the roleNames container.
/// </summary>
/// <param name="axUserId">
/// AX user id, e.g. curUserId()
/// </param>
/// <param name="roleNames">
/// container of role names to check. (use role NAME, not label.)
/// </param>
/// <returns>
/// true if user is in ANY of the specified roles.
/// </returns>
/// <remarks>
/// ajh 2014-02-12: previous method req'd admin perm. to run. Doh!
/// </remarks>

public static boolean isUserInRole(UserId axUserId, container roleNames)
{
    SecurityUserRole securityUserRole;
    SecurityRole securityRole;

    while select AotName from securityRole
    join securityUserRole
    where securityUserRole.User == axUserId
    && securityUserRole.SecurityRole == securityRole.RecId
    {
        if (conFind(roleNames, securityRole.AotName))
            return true;
    }
    return false;
}

So I guess the lesson here is to always test your code under a normal user account, and not to assume that the MSDN page for a given AX class will tell you everything you need to know about that class.

And, as with a lot of stuff in AX, I have a feeling that I’m still doing this “the wrong way”, even though my code works and is fairly simple. I’m guessing that, a year from now, I’ll have figured out that there’s a better way to do this.

I had a small issue crop up in AX a couple of weeks ago. It wasn’t big enough to spend any time on, but it was a bit of an annoyance. Well, I had some spare time yesterday, so I decided to see if I could fix it. The end result was that I did indeed fix it, but the journey to that point was kind of ridiculous, so I thought I’d write it up.

AX has a built-in compare tool, for comparing different versions of code in different AX layers, or in source control. It’s not a terribly great tool, and I’d rather have WinMerge or Beyond Compare, but it’s good enough. The initial form shows the names of the two files being compared, with a red box next to one, and a blue box next to the other, to indicate the colors that will be used to highlight the differences between the two files.

Well, the color in those little boxes mysteriously disappeared a couple of weeks ago. The tool still works, and the text is highlighted in red & blue, but there’s no visual indication of which text is from which file. Not a really big deal, but inconvenient.

Most of the tools built into AX are written in X++, and we have full source, so I went ahead and dug up the source for the form named “SysCompareForm.” I don’t think I should post any of the source here, but what I found is that those little red and blue boxes were actually HTML controls, each one displaying a web page, constructed in the code! I’d never really noticed before, but the boxes were not actually displaying solid red & blue, but rather were displaying red-to-white and blue-to-white gradients. And, of course, this being Microsoft, they were doing so in a way that only worked in older versions of IE. And, yeah, I’d recently upgraded IE on my VM from 8 to 10. So that was the problem: each of those little squares was actually rendering a web page with IE, just to get little red & blue swatches!

The cross-browser gradient situation has been a bit of a mess for a long time now, and you generally need to add about 10 lines to your CSS file just to do one gradient that works well across all browsers. So, I tried to update the code so it would render out OK in IE 10. Well, I messed around for a while, and couldn’t quite get it right. Then, I did some searching, and found this thread from a Russian web site, from someone else who had the problem and solved it. So, I just copied his code and went on with my life.

Apparently, this problem was fixed by Microsoft in a recent CU, but I guess it’s one that we haven’t applied yet. I wonder how much other stuff in AX is being done like this, and relying on HTML/CSS that only works in IE 8. Geez.