Creating a Generic Type at Runtime

I have a type (at runtime), I want to use it with an IOC container (in this case StructureMap) to find a generic implementation using this type. How do I do that?

It’s simpler than you’d think:

Type genericType = typeof (AbstractValidator);
Type type = genericType.MakeGenericType(bindingContext.ModelType);

//Structure Map container
var instance = _container.GetInstance(type);
In Code

Deploying with MsDeploy Outside of Visual Studio

Building the msdeploy package with MSBuild.

This requires MsDeploy to be installed on the build machine.

MSBUILD /T:Package /P:Configuration=QA;PackageLocation="C:\Build\Artifacts\eserve\DEV\QA\QA.zip"

Deploying the package with MsDeploy to a web site

How to get the msdeploy command.

-source:package='C:BuildArtifactseserveDEVQAQA.zip' -dest:auto,ComputerName='https://eserve-dev.sacda.org:8172/MsDeploy.axd?site=eserve-dev',UserName='conwayc',Password='austin_1',IncludeAcls='False',AuthType='Basic' 
-verb:sync 
-disableLink:AppPoolExtension 
-disableLink:ContentExtension 
-disableLink:CertificateExtension 
-allowUntrusted 
-retryAttempts=2

Copying the package with ROBOCOPY

Copying the package to another folder with robocopy has an issue. Robocopy uses exit codes as success/error codes. CI servers look at the exit code of a command to determine success or failure. Robocopy breaks this model. Luckliy the sql team posted a code snippet to get around this issue.

rem http://weblogs.sqlteam.com/robv/archive/2010/02/17/61106.aspx
robocopy %*
rem suppress successful robocopy exit statuses, only report genuine errors (bitmask 16 and 8 settings)
set/A errlev="%ERRORLEVEL% & 24"
rem exit batch file with errorlevel so SQL job can succeed or fail appropriately
exit/B %errlev%

Deploying from folder to site

-verb:sync -source:contentPath=C:BuildArtifactsSSOClientDEV -dest:contentPath="C:inetpubadfsls",computerName='http://customer.dev.myconsolidated.net
/MsDeployAgentService',userName=ccadmin,password=$urewest123

Change App Path at Commandline via MSBuild

/T:Package 
/P:Configuration=DEV;PackageLocation="C:\BuildArtifacts\Grover\Dev\Builds\DEV\Grover.zip";DeployIISAppPath=dev.grover.winnemen.com

Using MsBuild to deploy contents to folder

/T:PipelinePreDeployCopyAllFilesToOneFolder /P:Configuration=QA;_PackageTempDir="C:Build\Artifacts\Momntz\DEV\Builds\QA

Deploying Local with MSDeploy

"C:\Program Files\IIS\Microsoft Web Deploy V3\msdeploy.exe" -verb:sync -source:package='C:\BuildArtifacts\AlSupport.zip' -dest:auto,computerName='localhost' -allowUntrusted -retryAttempts=2 -verbose

Deploying folder to Azure with MSDeploy

The following command line is for deploying a folder to windows azure websites.

"C:\Program Files\IIS\Microsoft Web Deploy V3\msdeploy.exe" -verb:sync -source:contentPath="C:\TeamCity\buildAgent\work\d018513aed1c09f\Build" -dest:contentPath="groverqa",wmsvc=waws-prod-bay-005.publish.azurewebsites.windows.net/msdeploy.axd?site=groverqa,userName=$groverqa,password=secret,authtype='Basic' -AllowUntrusted
In Code

Code Refactor

On a recent project, I was tasked with refactoring large parts of a web system. It’s written in C#. Over time some of the code-behind files had grown to 4000 lines. The goal was to get this number down to a more maintainable level.

Over the next few posts, I’ve taken snippets of code that I refactored and will explain my thoughts and how I arrived at the solution.

The first code snippet:

    string tmp = Request.QueryString["st"];
    _varStartRecNum = tmp;
    if ((tmp != null) & (!Page.IsPostBack))
    {
        _varStartRecNum = tmp;
        postBack = true;
    }

    tmp = Request.QueryString["det"];
    if ((tmp != null) & (!Page.IsPostBack))
    {
        _varDetailsRecNum = tmp;
        postBack = true;
    }

    tmp = Request.QueryString["return"];
    if ((tmp != null) & (!Page.IsPostBack))
    {
        postBack = true;
    }

    tmp = Request.QueryString["searchnow"];
    if ((tmp != null) & (!Page.IsPostBack))
    {
        Session["selectedTab"] = "mtf";
        Session["sessionDSProviders"] = null;
        Session["mtfs"] = null;
    }

    tmp = Request.QueryString["displaywalking"];
    if (tmp == "true")
    {
        dispMtf = false;
        postBack = true;
    }

    tmp = Request.QueryString["sb"];

    if ((tmp != null) & (!Page.IsPostBack))
    {
        _varSortBy = tmp;
        postBack = true;
        switch (_varSortBy)
        {
            case "Distance":
            case "Drive time":
                ddlSortBy.SelectedIndex = 0;
                break;
            case "Name":
                ddlSortBy.SelectedIndex = 1;
                break;
            case "Gender":
                ddlSortBy.SelectedIndex = 2;
                break;
            case "Clinic":
                ddlSortBy.SelectedIndex = 3;
                break;
            case "City":
                ddlSortBy.SelectedIndex = 4;
                break;
            case "Description":
                ddlSortBy.SelectedIndex = 5;
                break;
        }
    }

The above code snippet is a collection of if statements, which are an evaluation and an execution. In my first attempt, I tried to use the same evaluation for all if statements, but then I realize one was different. Not understanding the intent of the code I am forced to preserve the logic in verbatim.

Different if evaluation:

tmp = Request.QueryString["displaywalking"];
if (tmp == "true")
{
    dispMtf = false;
    postBack = true;
}

The switch statement concerned me. The condition to enter into the switch statement is the same as the others. I decided to proceed and worry about the switch statement later.

The code uses the same variable, the ‘tmp’ variable, to retrieve different query value. The value is overwritten with each query value retrieval. For clarity I create a variable for each query value:

string st = Request.QueryString["st"];
string det = Request.QueryString["det"];
string @return = Request.QueryString["return"];
string searchNow = Request.QueryString["searchnow"];
string displayWaling = Request.QueryString["displaywalking"];
string sb = Request.QueryString["sb"];

The next step was to isolate the evaluation and expression while keeping them associated with each other. If an evaluation is true, I want to execute its corresponding expression. I created a class that represented the association.

private class Evaluate
{

    public Func Evaluation { get; set; }

    public Action Expression { get; set; }
}

Now I can create an evaluation, and if it’s true, I can execute its expression.

The next problem was how to use the above class with all the if statements. I was worried the expressions might get unwieldy in a collection. The whole purpose was to create a concise scaleable solution. The existing solution was neither.

var eval = new[]
               {
                   new Evaluate {Evaluation = () => (!string.IsNullOrEmpty(st) && !IsPostBack), Expression = () => { _varStartRecNum = st;postBack = true; }},
                   new Evaluate {Evaluation = () => (!string.IsNullOrEmpty(det) && !IsPostBack), Expression = () => { _varStartRecNum = det;postBack = true; }}, 
                   new Evaluate {Evaluation = () => (!string.IsNullOrEmpty(@return) && !IsPostBack), Expression = () => {postBack = true; }}, 
                   new Evaluate {Evaluation = () => (!string.IsNullOrEmpty(searchNow) && !IsPostBack), Expression = () => {Session["selectedTab"] = "mtf";Session["sessionDSProviders"] = null; Session["mtfs"] = null;}}, 
                   new Evaluate {Evaluation = () => (!string.IsNullOrEmpty(displayWaling)), Expression = () => {dispMtf = false; postBack = true;}}, 
                   new Evaluate {Evaluation = () => (!string.IsNullOrEmpty(sb) && !IsPostBack), Expression = () => {_varSortBy = sb;postBack = true; SetSort(_varSortBy);}}, 
               };

It turned out better than I expected. One drawback with my solution is, if you don’t know how to use delegates, you’ll be screwed when it comes to maintaining the above code.

The last stumbling block was the switch statement. It was not going to fit gracefully into my anonymous collection, but then it didn’t need to:

private void SetSort(string sortBy)
{
    switch (sortBy)
    {
        case "Distance":
        case "Drive time":
            ddlSortBy.SelectedIndex = 0;
            break;
        case "Name":
            ddlSortBy.SelectedIndex = 1;
            break;
        case "Gender":
            ddlSortBy.SelectedIndex = 2;
            break;
        case "Clinic":
            ddlSortBy.SelectedIndex = 3;
            break;
        case "City":
            ddlSortBy.SelectedIndex = 4;
            break;
        case "Description":
            ddlSortBy.SelectedIndex = 5;
            break;
    }
}

By encapsulating it into a method, I was able reference the method in the expression. It worked every nicely.

new Evaluate {Evaluation = () => (!string.IsNullOrEmpty(sb) && !IsPostBack), Expression = () => {_varSortBy = sb;postBack = true; SetSort(_varSortBy);}

The last component is iterating over the collection:

foreach (var evaluate in eval.Where(evaluate => evaluate.Evaluation()))
{
    evaluate.Expression();
}

The complete solution:

private class Evaluate
{
    public Func Evaluation { get; set; }

    public Action Expression { get; set; }
}

private void SetSort(string sortBy)
{
    switch (sortBy)
    {
        case "Distance":
        case "Drive time":
            ddlSortBy.SelectedIndex = 0;
            break;
        case "Name":
            ddlSortBy.SelectedIndex = 1;
            break;
        case "Gender":
            ddlSortBy.SelectedIndex = 2;
            break;
        case "Clinic":
            ddlSortBy.SelectedIndex = 3;
            break;
        case "City":
            ddlSortBy.SelectedIndex = 4;
            break;
        case "Description":
            ddlSortBy.SelectedIndex = 5;
            break;
    }
}

private void EvaluateQueryParameters()
{
    string st = Request.QueryString["st"];
    string det = Request.QueryString["det"];
    string @return = Request.QueryString["return"];
    string searchNow = Request.QueryString["searchnow"];
    string displayWaling = Request.QueryString["displaywalking"];
    string sb = Request.QueryString["sb"];

    var eval = new[]
                   {
                       new Evaluate {Evaluation = () => (!string.IsNullOrEmpty(st) && !IsPostBack), Expression = () => { _varStartRecNum = st;postBack = true; }},
                       new Evaluate {Evaluation = () => (!string.IsNullOrEmpty(det) && !IsPostBack), Expression = () => { _varStartRecNum = det;postBack = true; }}, 
                       new Evaluate {Evaluation = () => (!string.IsNullOrEmpty(@return) && !IsPostBack), Expression = () => {postBack = true; }}, 
                       new Evaluate {Evaluation = () => (!string.IsNullOrEmpty(searchNow) && !IsPostBack), Expression = () => {Session["selectedTab"] = "mtf";Session["sessionDSProviders"] = null; Session["mtfs"] = null;}}, 
                       new Evaluate {Evaluation = () => (!string.IsNullOrEmpty(displayWaling)), Expression = () => {dispMtf = false; postBack = true;}}, 
                       new Evaluate {Evaluation = () => (!string.IsNullOrEmpty(sb) && !IsPostBack), Expression = () => {_varSortBy = sb;postBack = true; SetSort(_varSortBy);}}, 
                   };

    foreach (var evaluate in eval.Where(evaluate => evaluate.Evaluation()))
    {
        evaluate.Expression();
    }
}

In the end, I like this solution better than the original. One of the drawbacks is the level it’s written. I wanted to create a simpler solution that any developer could maintain. There isn’t anything difficult about the above code; I’m creating a collection and iterating over it. The confusion comes in with the evaluation and the expressions. It’s not a beginner topic.

Weighted Random Distribution

This is genius; I could have used this a couple of years ago. I’m posting it here for safe keeping. Note that I am NOT using the random class. The random class is not truly random. It’s based on time. Time is predictable.

RNGCryptoServiceProvider rng = new RNGCryptoServiceProvider();

byte[] result = new byte[8];
rng.GetBytes(result);
double rand = (double)BitConverter.ToUInt64(result, 0) / ulong.MaxValue;

//40 percent chance of being selected.
if (rand > 0.40d )
{
 ...
}
In Code