I have a SharePoint 2013 farm, I created a new SharePoint solution as a sandbox solution and I can add a visual web part as a new item that was added successfully.
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When I built the solution, I faced this error.
Error 2 The name 'InitializeControl' does not exist in the current context
c:\users\awis\documents\visual studio 2017\Projects\SharePointProject\SharePointProject\VisualWebPart1\VisualWebPart1.ascx.cs
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How I can fix this error "The name 'InitializeControl' does not exist in the current context in SharePoint 2013"?