I'm developping a Windows app based on the Windows Form template. I'm using .NET 3.5 version. In this app, the goal is that all the visual settings of the different forms can be managed from the App.Config file (the background color, the background color of the different buttons etc...).
So basically, I have a "FormBase" class, of which all my forms inherit, and this class contains code like this :
public class FormBase : Form
{
protected override void OnLoad(EventArgs e)
{
BackColor = Color.FromName(ConfigurationManager.AppSettings["backColor"]);
foreach (var item in this.Controls)
{
if (item is Button)
{
((Button)item).BackColor = Color.FromName(ConfigurationManager.AppSettings["buttonBackground"]);
((Button)item).ForeColor = Color.FromName(ConfigurationManager.AppSettings["buttonText"]);
}
if (item is ...)
{
//some other code
}
}
}
}
And then I have my App.Config file which contains code like :
<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<appSettings>
<add key="buttonText" value="White"/>
<add key="buttonBackground" value="Red"/>
<add key="backColor" value="White"/>
<add key="textColor" value="Red"/>
</appSettings>
</configuration>
And now, in the declaration of all my forms I have the line
public partial class Form1 : FormBase
My problem is, when I run the app it runs fine, and it works, the different colors in the App.Config files are the colors displayed on my forms. But when I just look at the designer in Visual Studio without running the app, the designer can't display what the form will look like and I get the following error
The service System.Windows.Forms.Design.IEventHandlerService already exists in the service container. Parameter name: serviceType
And I don't know how to solve this. This isn't a huge problem since the app runs fine anyway, but this bothers me and I'd like to know what's happening