Visual Studio 2010: Why aren't key combinations available?

I am trying to use VS 2010 for writing C. Frequently, I try to use a hotkey combination, and I get an error message of the form:

The key combination (key, key) is bound to com开发者_StackOverflow社区mand (Command) which is not currently available.

Why is this? Examples include CTRL + R, R for Rename and CTRL + K, CTRL + D for Format Document.

I am trying these commands with my cursor in the code editing window.

I find that this works in 2008 C# but not 2010 C/C++.

---

As 020Z28 says, the commands aren't supported in the C++ text editor. The workaround for Format Document is to Select All then Format Selection: Ctrl A, Ctrl K, Ctrl F.

---

The C++ text editor does not implement those two commands. If they work in 2008, it's only because you have an extension installed that adds support for those features.

Edit: The OP currently says "for writing C", just in case the question later changes to "for writing C#."

If the OP actually means C#, then the error is occurring because you are editing a document that is not part of a project/solution you currently have open, or the file has the Build Action set to None.

---

I have at random found the format document command to be "not currently available". I have found that saving the file and switching to another tab and back, will renable the command.

---

It may depend on the file extension of the file you are trying to format.

For example, I was testing a BizTalk map (XSLT) which outputs XML. The output file had a .txt extension, and it repeatedly threw the Ctrl+K, Ctrl+D error. When I changed the file extension to .xml, Ctrl+K,Ctrl+D worked every time.

I don't know if VS uses the content or the extension to determine how to format the file, but my thinking is that VS has no idea how to format a .txt file, but it does know how to format a .xml file.

---

Remove 'tagprefix="asp"' property from register tag.