Using the Image Manager Dialog to get images from a database

[Roger Withnell]

I would like Image Manager to display a list of images from a database so that they can be inserted into the editor.

I am using asp.net 3.5, Visual Web Developer 2008 Express and VB.

I understand that to do this I need to build a Custom FileBrowserContent Provider as described in:

http://www.telerik.com/help/aspnet-ajax/customfilebrowsercontentprovider.html

I have created MyContentProvider class in MyCustomProvider namespace as per the above help page and added:

<%@ Register Namespace = "MyCustomProvider" TagPrefix = "MyCp" Assembly="App_Code" %>

But when I add:

RadEditor1.ImageManager.ContentProviderTypeName = "ContentProviders.RadEditor.MyContentProvider, App_Code" to my code behind, the Image Manager page has the following error:

Value cannot be null.
Parameter name: type
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.ArgumentNullException: Value cannot be null.
Parameter name: type

Source Error:

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below. 

Stack Trace:

[ArgumentNullException: Value cannot be null.
Parameter name: type]
   System.Activator.CreateInstance(Type type, BindingFlags bindingAttr, Binder binder, Object[] args, CultureInfo culture, Object[] activationAttributes) +7679178
   Telerik.Web.UI.RadFileExplorer.InitContentProvider(String selectedUrl) +226
   Telerik.Web.UI.RadFileExplorer.InitContentProvider() +138
   Telerik.Web.UI.RadFileExplorer.BindExplorer() +48
   Telerik.Web.UI.RadFileExplorer.OnLoad(EventArgs e) +139
   System.Web.UI.Control.LoadRecursive() +50
   System.Web.UI.Control.LoadRecursive() +141
   System.Web.UI.Control.LoadRecursive() +141
   System.Web.UI.Control.LoadRecursive() +141
   System.Web.UI.Control.LoadRecursive() +141
   System.Web.UI.Control.LoadRecursive() +141
   System.Web.UI.Control.LoadRecursive() +141
   System.Web.UI.Control.LoadRecursive() +141
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +627

I've also tried setting it with the example (from the Help page above):

RadEditor1.FileBrowserContentProviderTypeName = typeof(DatabaseContentProvider).AssemblyQualifiedName

but I don't know the VB syntax for this.

Your help would be much appreciated.

Thanking you in anticipation.

Roger

 

[Fiko]

Hi Roger,

In your case I recommend you use this approach in order to set the content provider to the RadEditor control:

RadEditor1.FileBrowserContentProviderTypeName = GetType(DatabaseContentProvider).AssemblyQualifiedName

I hope this helps.

Regards,
Fiko
the Telerik team

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[humayoo]

Hello,

i am getting  error when i used 'Gettype' instead of 'typeof'. please see the attachment for error details.

thanks
Humayoo

[Rumen]

Hello Humayoo,

Have you tried the following syntax:

ImageManagerParameters.FileBrowserContentProviderTypeName =
typeof(Telerik.Web.Examples.DBContentProvider).AssemblyQualifiedName;

Kind regards,
Rumen
the Telerik team

[humayoo]

Hi,

if i used  "ImageManagerParameters.FileBrowserContentProviderTypeName = typeof(Telerik.Web.Examples.DBContentProvider).AssemblyQualifiedName;" , i get this error sometimes. please see attachment also  about error details.

Server Error in '/myproject' Application.

Value cannot be null.
Parameter name: type

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.ArgumentNullException: Value cannot be null.
Parameter name: type

Source Error:

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

Stack Trace:

[ArgumentNullException: Value cannot be null. Parameter name: type] System.Activator.CreateInstance(Type type, BindingFlags bindingAttr, Binder binder, Object[] args, CultureInfo culture, Object[] activationAttributes) +7681290 Telerik.Web.UI.RadFileExplorer.InitContentProvider(String selectedUrl) +228 Telerik.Web.UI.RadFileExplorer.InitContentProvider() +140 Telerik.Web.UI.RadFileExplorer.get_ContentProvider() +24 Telerik.Web.UI.RadFileExplorer.BindExplorer() +48 Telerik.Web.UI.RadFileExplorer.OnLoad(EventArgs e) +139 System.Web.UI.Control.LoadRecursive() +50 System.Web.UI.Control.LoadRecursive() +141 System.Web.UI.Control.LoadRecursive() +141 System.Web.UI.Control.LoadRecursive() +141 System.Web.UI.Control.LoadRecursive() +141 System.Web.UI.Control.LoadRecursive() +141 System.Web.UI.Control.LoadRecursive() +141 System.Web.UI.Control.LoadRecursive() +141 System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +627

---

Version Information: Microsoft .NET Framework Version:2.0.50727.5446; ASP.NET Version:2.0.50727.5420

here is my code for image manager

DialogOpener DialogOpener1 =e.Item.FindControl("DialogOpener1") as DialogOpener;
                FileManagerDialogParameters imageManagerParameters = new FileManagerDialogParameters();
                imageManagerParameters.ViewPaths = new string[] { "~/imagefolder/A" };
                imageManagerParameters.UploadPaths = new string[] { "~/imagefolder/A" };
                imageManagerParameters.DeletePaths = new string[] { "~/imagefolder/A" };
                imageManagerParameters.MaxUploadFileSize = 5242880;
                imageManagerParameters.FileBrowserContentProviderTypeName = typeof(ChangeImageSizeProvider).AssemblyQualifiedName;

                // If you don't set the following property, the default value will be used
                imageManagerParameters.SearchPatterns = new string[] { "*.jpg", "*.gif", "*.png" };

                DialogDefinition imageManager = new DialogDefinition(typeof(ImageManagerDialog), imageManagerParameters);
                imageManager.ClientCallbackFunction = "ImageManagerFunction";
                imageManager.Width = Unit.Pixel(750);
                imageManager.Height = Unit.Pixel(440);
                imageManager.Parameters["EnableImageEditor"] = false;




                //If you need to customize the dialog then register the external dialog files
                imageManager.Parameters["ExternalDialogsPath"] = "~/EditorDialogs/";

                DialogOpener1.DialogDefinitions.Add("ImageManager", imageManager);

[Rumen]

Hello Humayoo,

Do you get the mentioned error when using the built-in content provider? Please, remove the
   imageManagerParameters.FileBrowserContentProviderTypeName = typeof(ChangeImageSizeProvider).AssemblyQualifiedName;
line and test again.

I also noticed that you have set the ExternalDialogsPath property and most likely you have customized the dialog. Please remove the imageManager.Parameters["ExternalDialogsPath"] = "~/EditorDialogs/"; line and see whether the customization is causing the problem.

My suggestion is to also test your code with the latest version of RadControls for ASP.NET AJAX Q2 2011, where it could be fixed. Please, note that it does not support .NET 2.0 and you should test it with 3.5 or 4.0.

Best regards,
Rumen
the Telerik team

[humayoo]

Hello,

 thanks for reply. i am using custom content provider. i can not use latest rad control because i am using sitefinity 3.7. this controls dll from sitefinity 3.7

thanks
Humayoo

[Rumen]

Hello Humayoo,

You can see how to upgrade to the latest version in Sitefinity in this KB article: How to upgrade RadControls. If you would like you can wait for Q2 2011 SP1 that will be released later this week.

Best regards,
Rumen
the Telerik team

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