Is it possible to exclude files in a project from Xcode when searching? I have some JSON files in my project and Xcode constantly locks up if it finds matches in these files.
You can define custom search scope for your search. Custom scope can be define, save, and reuse specific location and file criteria for searches.

Now you can add as as many file names as you want.

More details on how to use custom search scope can be found here- https://developer.apple.com/Library/ios/recipes/xcode_help-search_navigator/articles/adding_a_search_scope.html
I prefere to use regexp. example for excluding unit tests files "foo_unittest.cc" or "foo_test.m"
^.((?!test).)*$
dropdown fields conditions:
- "File name"
- "matches regular expression"
来源:https://stackoverflow.com/questions/24603639/exclude-a-file-from-xcode-when-searching