“Cannot save the property settings for this Web Part” error when using SmartPart in SharePoint

I recently deployed a custom user control using SmartPart on SharePoint 2007, and although everything else seemed to work fine, I came across the following error when trying to edit the properties (in my case, the chrome type and width):

Cannot save the property settings for this Web Part. Exception occurred. (Exception from HRESULT: 0×80020009 (DISP_E_EXCEPTION))

I managed to resolve this, thanks to an MSDN forum post, by changing one of my lines of code:

using (SPSite oSiteCollection = SPContext.Current.Site)

to the slightly more long-winded:

using (SPSite oSiteCollection = new SPSite(SPContext.Current.Site.ID))

I’m not sure why using SPContext.Current.Site directly (versus creating a new SPSite object) causes this behaviour, but at least it’s a simple fix.

How to check whether a SharePoint user is in a particular group

Here’s a quick function I wrote to check whether a user is a member of a particular SharePoint group:

private bool IsMemberOf(string groupName)
{
    SPUser user = SPContext.Current.Web.CurrentUser;

    try
    {
        if (user.Groups[groupName] != null)
            return true;
        else
            return false;
    }
    catch
    {
        return false;
    }
}

The try-catch is required as – somewhat counter-intuitively – SharePoint seems to throw a “Group not found” error if the user is not a member of the group.

How to set SharePoint page title programmatically

I’ve spent some time today trying to figure out how to set the title of a SharePoint page from my own code. As blogger Michael Becker rightly points out, you can’t simply set Page.Title.

The correct solution, as provided by Michael, is illustrated in this example C# code:

// Get a reference to the appropriate Content Placeholder
ContentPlaceHolder contentPlaceHolder = (ContentPlaceHolder) 
                       Page.Master.FindControl("PlaceHolderPageTitle");

// Clear out anything that SharePoint might have put in it already
contentPlaceHolder.Controls.Clear();

// Put your content in
LiteralControl literalControl = new LiteralControl();
literalControl.Text = "Your text goes here";
contentPlaceHolder.Controls.Add(literalControl);

Happily this even works when you “cheat” by hosting an ASP.NET user control within a SmartPart, as opposed to creating a bona fide Web Part.

Deploy ASP.NET web user controls on SharePoint using SmartPart

Today I’ve been playing with Return of SmartPart 1.3,  a shim which allows you to create SharePoint 2007 web parts using Web User Controls (ASCX files) created by Visual Studio/Visual Web Developer.

This is probably the least painful way for C#/VB.NET developers to delve into web part building without having to worry too much about the intricacies of the SharePoint platform.

Complete with setup wizard, comprehensive user guide and sample user controls, it’s a snap to get running, although you will need access to your SharePoint server both to install the SmartPart and any custom user controls. It also optionally supports AJAX controls, after installing Microsoft’s ASP.NET AJAX extensions.

There’s no need to use strong naming or even compile your controls – just drop the .ascx (and .ascx.cs/.vb, if necessary) files into your usercontrols directory and you’re good to go.