I assume that you already have knowledge of working with the Ribbon in SharePoint 2010 and in particular using javascript page components. The snippets assume you have the rest of the ribbon definition in place and an existing page component file. If you don’t, I’d recommend you head on over to Chris O’Brien’s great articles on ribbon customisations.

Creating the button.

First up we need to declare the button we wish to disable or rather enable based on the users permission.

<Button
  Id="Ribbon.MyButton.Button"
  Alt="Ribbon.MyButton.Button"
  Command="Ribbon.MyButton.Button.Configure"
  Image16by16="/_layouts/images/splogo.gif"
  Image32by32="/_layouts/images/settingsIcon.png"
  LabelText="Configure"
  Sequence="10"
  TemplateAlias="o1"
  ToolTipTitle="Configure"
  ToolTipDescription="Configure merge" />

The above definition is just that of an ordinary ribbon button, nothing special is declared in there.

Javascript page component.

The next step is to modify our page component file.

canHandleCommand: function (commandId) {
      if(commandId === 'Ribbon.MyButton.Button.Configure')
        {
            if(userIsContrib == null)
            {
                checkUserIsContrib();                 

                return false;
            }
            else
            {
                return userIsContrib;
            }
        }
        else {
            return false;
        }
    },

...

var userIsContrib = null;

function checkUserIsContrib() {
    var context = SP.ClientContext.get_current();
    var web = context.get_web();
    list = web.get_lists().getById(SP.ListOperation.Selection.getSelectedList());

    context.load(list,'EffectiveBasePermissions');

    context.executeQueryAsync(Function.createDelegate(this, gotUserIsContrib), Function.createDelegate(this, failedUserIsContrib));
}

function gotUserIsContrib() {

    // update the variable based on the users permission
    userIsContrib = list.get_effectiveBasePermissions().has(SP.PermissionKind.editListItems);

    //Update the UI
    RefreshCommandUI();

}

function failedUserIsContrib() {
    alert("failed failedUserIsContrib");
}

Because we want to check the user permissions asynchronously, we need to set userIsContrib initially to null. This will disable the button for all users while the checkUserIsContrib() method goes off and checks the users permissions.

After checking the users permissions and settings the flag appropriately we call RefreshCommandUI() which will again cause canHandleCommand to be run again. This time it will return the value that was set in the gotUserIsContrib() method. As a value has now been set on userIsContrib, no more checks against the server will be made by any other calls to RefreshCommandUI.

References.

•  Chris O’Brien: Customizing the ribbon
• Andrew Connell: Asynchronously Checking if a Command is Available in the SharePoint Ribbon

First up, we need a manifest file. This tells the environment what we would like it to do with the assembly.
Create a new xml file in the root of your project called manifest.xml and add the following code:

<?xml version="1.0" encoding="utf-8" ?>
<Solution xmlns="http://schemas.microsoft.com/sharepoint/"
  SolutionId="<new guid>">
  <Assemblies>
    <Assembly Location="<assembly>.dll" DeploymentTarget="GlobalAssemblyCache"></Assembly>
  </Assemblies>
</Solution>

Replace <new guid> with a generated GUID and <assembly> with the name of your dll file.
The DeploymentTarget attribute above specifies that it will be deployed to the GAC, you can use WebApplication if you want it to be deployed to the bin directory of your Webb Application.

You can also specify that the relevant line can be added to the SafeControls section of your web.config file by adding the following inside the Assembly tag above.

<SafeControls>
        <SafeControl Assembly="<assembly>, Version=1.0.0.0, Culture=neutral, PublicKeyToken=<public key token>" Namespace="<namespace>" TypeName="*" Safe="True" />
      </SafeControls>

Next up, create a ddf file in the root of your project. I tend to name mine wsp.ddf for consistency. This will contain the instructions on what to package into the wsp file. This file should look like the following.

;Define the output directory and CAB file name (with a wsp extension)
.Set DiskDirectory1="bin\Debug"
.Set CabinetNameTemplate="MySolutionName.wsp"
 
;Include the following files in the CAB Root
manifest.xml
bin\Debug\<assembly>.dll

Now all we have left to do is add a post build event to build the wsp for us.
Go to you project properties (right click project)
Under the Build Events tab under Post-build event command line, enter the following:

:: Change directory to the root of the project
cd "$(ProjectDir)"
 
:: Create a WSP CAB
MakeCAB /f "WSP.DDF"

You can change when the post build event runs, to your liking; normally ‘On successful build’.

That’s it when you have a successful build the wsp file will be generated ready for you to deploy, no more manual copying or editing web.config.

if (!SPContext.Current.Web.UserIsSiteAdmin)
              SPUtility.HandleAccessDenied(new Exception("You need to be a site administrator to access this page."));

This will redirect the user to the built in SharePoint Access denied page, for consistency.

The answer to this to create a validator in your webpart and hook it into the TextBox element of the DateTimeControl, which will then allow you to set the validation group on it.

To do this use the following code when you create your validator.

valReviewDate.ControlToValidate = string.Format("{0}${0}Date", dteReview.ID);

This post, describes how to do it from code in front.