designer errors: Object reference not set to an instance of an object_altiumdesigner打开工程报错object reference not set-优快云博客

本文解决了一个在尝试打开项目中某些表单的设计人员时出现的对象引用未设置到对象实例的错误。通过删除项目名称.csproj.user文件，问题得到了解决。

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I am getting the following error when I try to open the designer for some of the forms in my project. I have no clue why this is happening.

thanks

Object reference not set to an instance of an object.

at Microsoft.CompactFramework.Design.DeviceTypeResolutionService.EnsurePopulated(Boolean fPopulateProject)
at Microsoft.CompactFramework.Design.DeviceTypeResolutionService.SearchNormalEntries(AssemblyName assemblyName, String typeName, Boolean ignoreTypeCase, Boolean reflectionBased, Assembly& assembly)
at Microsoft.CompactFramework.Design.DeviceTypeResolutionService.SearchEntries(AssemblyName assemblyName, String typeName, Boolean ignoreTypeCase, Boolean reflectionBased, Assembly& assembly)
at Microsoft.CompactFramework.Design.DeviceTypeResolutionService.GetDeviceType(String typeName, Boolean throwOnError, Boolean ignoreCase)
at Microsoft.CompactFramework.Design.DeviceTypeResolutionService.GetType(String typeName, Boolean throwOnError, Boolean ignoreCase, ReferenceType refType)
at Microsoft.VisualStudio.Design.Serialization.CodeDom.AggregateTypeResolutionService.GetType(String name, Boolean throwOnError, Boolean ignoreCase)
at Microsoft.VisualStudio.Design.Serialization.CodeDom.AggregateTypeResolutionService.GetType(String name)
at System.ComponentModel.Design.DesignerHost.System.ComponentModel.Design.IDesignerHost.GetType(String typeName)
at System.ComponentModel.Design.Serialization.CodeDomDesignerLoader.EnsureDocument(IDesignerSerializationManager manager)
at System.ComponentModel.Design.Serialization.CodeDomDesignerLoader.PerformLoad(IDesignerSerializationManager manager)
at Microsoft.VisualStudio.Design.Serialization.CodeDom.VSCodeDomDesignerLoader.PerformLoad(IDesignerSerializationManager serializationManager)
at Microsoft.VisualStudio.Design.Serialization.CodeDom.VSCodeDomDesignerLoader.DeferredLoadHandler.Microsoft.VisualStudio.TextManager.Interop.IVsTextBufferDataEvents.OnLoadCompleted(Int32 fReload)

解决方案：

For a C# project I followed what mtm_king said + deleted the <project_name>.csproj.user file. And everything works fine now

原帖链接：http://social.msdn.microsoft.com/Forums/en/winformsdesigner/thread/4ceb2dd3-c760-495f-83e6-1bf2a54fda93