Csharp, how to call a form object from a tray based application [duplicate]

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C#, how to call a form object from a tray based application

Hi guys,

Iam trying to load a form class from a program running as a tray icon that originally used "FileList frmFileList = new FileList();" Now instead of a filelist I want to use a custom form but I get the error: Error 1 'System.Windows.Forms.Control.ControlCollection' does not contain a definition for 'Cast' and no extension method 'Cast' acceptin开发者_运维技巧g a first argument of type 'System.Windows.Forms.Control.ControlCollection' could be found (are you missing a using directive or an assembly reference?) Any ideas?

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It sounds like you forgot using System.Linq; at the top of your source file. But since you didn't post the sources, I can't say for sure. Posting the line of code that causes the error message, and the using directives that are in that same file would help.