diff --git a/clang/lib/Format/UnwrappedLineParser.cpp b/clang/lib/Format/UnwrappedLineParser.cpp
--- a/clang/lib/Format/UnwrappedLineParser.cpp
+++ b/clang/lib/Format/UnwrappedLineParser.cpp
@@ -466,7 +466,7 @@
               (NextTok->is(tok::semi) &&
                (!ExpectClassBody || LBraceStack.size() != 1)) ||
               (NextTok->isBinaryOperator() && !NextIsObjCMethod);
-          if (NextTok->is(tok::l_square)) {
+          if (!Style.isCSharp() && NextTok->is(tok::l_square)) {
             // We can have an array subscript after a braced init
             // list, but C++11 attributes are expected after blocks.
             NextTok = Tokens->getNextToken();
diff --git a/clang/unittests/Format/FormatTestCSharp.cpp b/clang/unittests/Format/FormatTestCSharp.cpp
--- a/clang/unittests/Format/FormatTestCSharp.cpp
+++ b/clang/unittests/Format/FormatTestCSharp.cpp
@@ -316,6 +316,27 @@
                "    }\n"
                "}\n",
                Style);
+
+  verifyFormat("public A : Base\n"
+               "{\n"
+               "}\n"
+               "[Test]\n"
+               "public Foo()\n"
+               "{\n"
+               "}\n",
+               Style);
+
+  verifyFormat("namespace\n"
+               "{\n"
+               "public A : Base\n"
+               "{\n"
+               "}\n"
+               "[Test]\n"
+               "public Foo()\n"
+               "{\n"
+               "}\n"
+               "}\n",
+               Style);
 }
 
 TEST_F(FormatTestCSharp, CSharpSpaceBefore) {