Qt QJsonDocument::fromBinaryData() does not work

Question

下面是简单的代码:

QByteArray ba  = jdoc.toBinaryData();
QJsonDocument jdoc2;
jdoc2.fromBinaryData(ba);
qDebug() << jdoc.isNull();
qDebug() << jdoc2.isNull();

Result: jdoc not null, but jdoc2 is null。我做错了什么?看起来jdoc2.fromBinaryData(ba);根本不起作用。我使用Qt 5.5.0

Answer 1

QJsonDocument::fromBinaryData是一个静态方法。你需要写:

jdoc2 = QJsonDocument::fromBinaryData( ba );

Answer 2

fromBinaryData是一个静态函数:您的调用不会影响jdoc2。试试下面的命令:

QByteArray ba  = jdoc.toBinaryData();
QJsonDocument jdoc2 = QJsonDocument::fromBinaryData(ba);