在 VisualStudio 中更改项目命名空间

Right click properties, Application tab, then see the assembly name and default namespace

You can change the default namespace:
-> Project -> XXX Properties...
On Application tab: Default namespace

Other than that:
Ctrl-H
Find: WindowsFormsApplication16
Replace: MyName

Assuming this is for a C# project and assuming that you want to change the default namespace, you need to go to Project Properties, Application tab, and specify "Default Namespace".

Default namespace is the namespace that Visual studio sets when you create a new class. Next time you do Right Click > Add > Class it would use the namespace you specified in the above step.

Instead of Find & Replace, you can right click the namespace in code and Refactor -> Rename.

Thanks to @Jimmy for this.

Just right click on the name you want to change (this could be namespace or whatever else) and select Refactor->Rename...

Enter new name, leave location as [Global Namespace], check preview if you want and you're done!

"Default Namespace textbox in project properties is disabled" Same with me (VS 2010). I edited the project file ("xxx.csproj") and tweaked the item. That changed the default namespace.

First)

1. Goto menu: Project -> WindowsFormsApplication16 Properties/
2. write MyName in Assembly name and Default namespace textbox, then save.

Second)

1. open one old .cs file ( a class or a form)
2. right click on WindowsFormsApplication16 in front of namespace, goto Refactor -> Rename .
3. write MyName in New name textbox, in Rename Message Box.
4. press Ok, then Apply

In visual studio right-click on your project then select Edit Project File or open the .csproj file directly then inside the <PropertyGroup> tag write the following tag

<RootNamespace>YourNamespaceName</RootNamespace>