diff options
| -rw-r--r-- | src/corelib/doc/snippets/code/src_corelib_text_qbytearray.cpp | 14 | ||||
| -rw-r--r-- | src/corelib/text/qbytearray.cpp | 8 |
2 files changed, 20 insertions, 2 deletions
diff --git a/src/corelib/doc/snippets/code/src_corelib_text_qbytearray.cpp b/src/corelib/doc/snippets/code/src_corelib_text_qbytearray.cpp index 74f14f2a4b..196c992c8e 100644 --- a/src/corelib/doc/snippets/code/src_corelib_text_qbytearray.cpp +++ b/src/corelib/doc/snippets/code/src_corelib_text_qbytearray.cpp @@ -504,6 +504,16 @@ qDebug(ba.constData()); QByteArray ba = QByteArrayLiteral("byte array contents"); //! [53] +//! [54] +QByteArray ba("abc"); +const char big[10] = "abc"; +ba.compare(big); // returns -1, big is longer than ba + +// In contrast: +const char arr[] = "abc"; +ba.compare(arr); // returns 0, both have the same size and data + +const char *str = "abc"; +ba.compare(str); // returns 0, the size is determined by scanning for '\0' +//! [54] } - - diff --git a/src/corelib/text/qbytearray.cpp b/src/corelib/text/qbytearray.cpp index aee22edc6f..b5327280f9 100644 --- a/src/corelib/text/qbytearray.cpp +++ b/src/corelib/text/qbytearray.cpp @@ -847,6 +847,14 @@ QByteArray qUncompress(const uchar* data, int nbytes) such a pointer, without a length, will interpret it as this sequence of bytes. Such a sequence, by construction, cannot contain a '\\0' byte. + Take care when passing fixed size C arrays to QByteArray methods that accept + a QByteArrayView: the length of the data on which the method will operate is + determined by array size. A \c{char [N]} array will be handled as a view of + size \c{N-1}, on the expectation that the array is a string literal with a '\\0' + at index \c{N-1}. For example: + + \snippet code/src_corelib_text_qbytearray.cpp 54 + Other overloads accept a start-pointer and a byte-count; these use the given number of bytes, following the start address, regardless of whether any of them happen to be '\\0' bytes. In some cases, where there is no overload |