QJsonValueConstRef Class

The QJsonValueConstRef class is a read-only reference to a value inside an array or object. More…

List of all members, including inherited members

Public Functions

Detailed Description

Its instances are what the const iterators of QJsonArray and QJsonObject return. It reads the element each time it is used, so it behaves like a const QJsonValue & and converts to QJsonValue when copied into one.

See also QJsonValueRef and QJsonValue.

Differences from Qt

Member Function Documentation

QJsonValueConstRef::QJsonValueConstRef(const QJsonValueConstRef &)

Creates a copy of the reference; both refer to the same element.

bool QJsonValueConstRef::isArray() const

Returns true if the element is an array.

bool QJsonValueConstRef::isBool() const

Returns true if the element is a bool.

bool QJsonValueConstRef::isDouble() const

Returns true if the element is a number.

bool QJsonValueConstRef::isNull() const

Returns true if the element is null.

bool QJsonValueConstRef::isObject() const

Returns true if the element is an object.

bool QJsonValueConstRef::isString() const

Returns true if the element is a string.

bool QJsonValueConstRef::isUndefined() const

Returns true if the element is undefined, which it is when the reference is out of range.

QJsonValue QJsonValueConstRef::operator[](const QString &key) const

Returns the value that key maps to if the element is an object, and an undefined value otherwise.

QJsonValue QJsonValueConstRef::operator[](QStringView key) const

This is an overloaded function.

QJsonValue QJsonValueConstRef::operator[](QLatin1StringView key) const

This is an overloaded function.

template <typename K, typename = std::enable_if_t<QtPrivate::IsJsonCString<K>>>QJsonValue QJsonValueConstRef::operator[](K &&key) const

This is an overloaded function.

Looks key up when it is a C string, such as a string literal.

QJsonValue QJsonValueConstRef::operator[](qsizetype i) const

This is an overloaded function.

Returns the item at index i if the element is an array, and an undefined value otherwise.

QJsonArray QJsonValueConstRef::toArray() const

Returns the element as an array, or an empty array if it is not one.

See also QJsonValue::toArray().

QJsonArray QJsonValueConstRef::toArray(const QJsonArray &defaultValue) const

This is an overloaded function.

Returns the element as an array, or defaultValue if it is not one.

bool QJsonValueConstRef::toBool(bool defaultValue = false) const

Returns the element as a bool, or defaultValue if it is not one.

See also QJsonValue::toBool().

double QJsonValueConstRef::toDouble(double defaultValue = 0) const

Returns the element as a double, or defaultValue if it is not a number.

See also QJsonValue::toDouble().

int QJsonValueConstRef::toInt(int defaultValue = 0) const

Returns the element as an int, or defaultValue if it is not a whole number that fits.

See also QJsonValue::toInt().

qint64 QJsonValueConstRef::toInteger(qint64 defaultValue = 0) const

Returns the element as a qint64, or defaultValue if it is not a whole number that fits.

See also QJsonValue::toInteger().

QJsonObject QJsonValueConstRef::toObject() const

Returns the element as an object, or an empty object if it is not one.

See also QJsonValue::toObject().

QJsonObject QJsonValueConstRef::toObject(const QJsonObject &defaultValue) const

This is an overloaded function.

Returns the element as an object, or defaultValue if it is not one.

QString QJsonValueConstRef::toString() const

Returns the element as a string, or a null string if it is not one.

See also QJsonValue::toString().

QString QJsonValueConstRef::toString(const QString &defaultValue) const

This is an overloaded function.

Returns the element as a string, or defaultValue if it is not one.

QJsonValue::Type QJsonValueConstRef::type() const

Returns the type of the element.