QCborStreamReader¶
The
QCborStreamReader
class is a simple CBOR stream decoder, operating on either aQByteArray
orQIODevice
. More…
New in version 5.12.
Synopsis¶
Functions¶
def
addData
(data)def
addData
(data, len)def
addData
(data, len)def
clear
()def
containerDepth
()def
currentOffset
()def
currentStringChunkSize
()def
device
()def
enterContainer
()def
hasNext
()def
isArray
()def
isBool
()def
isByteArray
()def
isContainer
()def
isDouble
()def
isFalse
()def
isFloat16
()def
isFloat
()def
isInteger
()def
isInvalid
()def
isLengthKnown
()def
isMap
()def
isNegativeInteger
()def
isNull
()def
isSimpleType
()def
isSimpleType
(st)def
isString
()def
isTag
()def
isTrue
()def
isUndefined
()def
isUnsignedInteger
()def
isValid
()def
lastError
()def
leaveContainer
()def
length
()def
next
([maxRecursion=10000])def
parentContainerType
()def
readByteArray
()def
readString
()def
reparse
()def
reset
()def
setDevice
(device)def
toBool
()def
toDouble
()def
toFloat
()def
toInteger
()def
toSimpleType
()def
toUnsignedInteger
()def
type
()
Detailed Description¶
This class can be used to decode a stream of CBOR content directly from either a
QByteArray
or aQIODevice
. CBOR is the Concise Binary Object Representation, a very compact form of binary data encoding that is compatible with JSON. It was created by the IETF Constrained RESTful Environments (CoRE) WG, which has used it in many new RFCs. It is meant to be used alongside the CoAP protocol .
QCborStreamReader
provides a StAX-like API, similar to that ofQXmlStreamReader
. Using it requires a bit of knowledge of CBOR encoding. For a simpler API, seeQCborValue
and especially the decoding functionfromCbor()
.Typically, one creates a
QCborStreamReader
by passing the sourceQByteArray
orQIODevice
as a parameter to the constructor, then pop elements off the stream if there were no errors in decoding. There are three kinds of CBOR types:
Kind
Types
Behavior
Fixed-width
Integers, Tags, Simple types, Floating point
Value is pre-parsed by
QCborStreamReader
, so accessor functions areconst
. Must callnext()
to advance.Strings
Byte arrays, Text strings
Length (if known) is pre-parsed, but the string itself is not. The accessor functions are not const and may allocate memory. Once called, the accessor functions automatically advance to the next element.
Containers
Arrays, Maps
Length (if known) is pre-parsed. To access the elements, you must call
enterContainer()
, read all elements, then callleaveContainer()
. That function advances to the next element.So a processor function typically looks like this:
void handleStream(QCborStreamReader &reader) { switch (reader.type()) case QCborStreamReader::UnsignedInteger: case QCborStreamReader::NegativeInteger: case QCborStreamReader::SimpleType: case QCborStreamReader::Float16: case QCborStreamReader::Float: case QCborStreamReader::Double: handleFixedWidth(reader); reader.next(); break; case QCborStreamReader::ByteArray: case QCborStreamReader::String: handleString(reader); break; case QCborStreamReader::Array: case QCborStreamReader::Map: reader.enterContainer(); while (reader.lastError() == QCborError::NoError) handleStream(reader); if (reader.lastError() == QCborError::NoError) reader.leaveContainer(); } }
CBOR support¶
The following table lists the CBOR features that
QCborStreamReader
supports.
Feature
Support
Unsigned numbers
Yes (full range)
Negative numbers
Yes (full range)
Byte strings
Yes
Text strings
Yes
Chunked strings
Yes
Tags
Yes (arbitrary)
Booleans
Yes
Null
Yes
Undefined
Yes
Arbitrary simple values
Yes
Half-precision float (16-bit)
Yes
Single-precision float (32-bit)
Yes
Double-precision float (64-bit)
Yes
Infinities and NaN floating point
Yes
Determinate-length arrays and maps
Yes
Indeterminate-length arrays and maps
Yes
Map key types other than strings and integers
Yes (arbitrary)
Dealing with invalid or incomplete CBOR streams¶
QCborStreamReader
is capable of detecting corrupt input on its own. The library it uses has been extensively tested against invalid input of any kind and is quite able to report errors. If any is detected,QCborStreamReader
will setlastError()
to a value besidesNoError
, indicating which situation was detected.Most errors detected by
QCborStreamReader
during normal item parsing are not recoverable. The code usingQCborStreamReader
may opt to handle the data that was properly decoded or it can opt to discard the entire data.The only recoverable error is
EndOfFile
, which indicates that more data is required in order to complete the parsing. This situation is useful when data is being read from an asynchronous source, such as a pipe (QProcess
) or a socket (QTcpSocket
,QUdpSocket
,QNetworkReply
, etc.). When more data arrives, the surrounding code needs to call eitheraddData()
, if parsing from aQByteArray
, orreparse()
, if it is instead reading directly a the QIDOevice that now has more data available (seesetDevice()
).See also
- class PySide2.QtCore.QCborStreamReader¶
PySide2.QtCore.QCborStreamReader(device)
PySide2.QtCore.QCborStreamReader(data)
PySide2.QtCore.QCborStreamReader(data, len)
PySide2.QtCore.QCborStreamReader(data, len)
- param device:
- param data:
- param len:
long long
Creates a
QCborStreamReader
object with no source data. After construction,QCborStreamReader
will report an error parsing.You can add more data by calling
addData()
or by setting a different source device usingsetDevice()
.This is an overloaded function.
Creates a
QCborStreamReader
object that will parse the CBOR stream found by reading fromdevice
.QCborStreamReader
does not take ownership ofdevice
, so it must remain valid until this object is destroyed.
- PySide2.QtCore.QCborStreamReader.Type¶
This enumeration contains all possible CBOR types as decoded by
QCborStreamReader
. CBOR has 7 major types, plus a number of simple types carrying no value, and floating point values.Constant
Description
QCborStreamReader.UnsignedInteger
(Major type 0) Ranges from 0 to 2 64 - 1 (18,446,744,073,709,551,616)
QCborStreamReader.NegativeInteger
(Major type 1) Ranges from -1 to -2 64 (-18,446,744,073,709,551,616)
QCborStreamReader.ByteArray
(Major type 2) Arbitrary binary data.
QCborStreamReader.ByteString
An alias to .
QCborStreamReader.String
(Major type 3) Unicode text, possibly containing NULs.
QCborStreamReader.TextString
An alias to String
QCborStreamReader.Array
(Major type 4) Array of heterogeneous items.
QCborStreamReader.Map
(Major type 5) Map/dictionary of heterogeneous items.
QCborStreamReader.Tag
(Major type 6) Numbers giving further semantic value to generic CBOR items. See
QCborTag
for more information.QCborStreamReader.SimpleType
(Major type 7) Types carrying no further value. Includes booleans (true and false), null, undefined.
QCborStreamReader.Float16
IEEE 754 half-precision floating point (
qfloat16
).QCborStreamReader.HalfFloat
An alias to Float16.
QCborStreamReader.Float
IEEE 754 single-precision floating point (
float
).QCborStreamReader.Double
IEEE 754 double-precision floating point (
double
).QCborStreamReader.Invalid
Not a valid type, either due to parsing error or due to reaching the end of an array or map.
- PySide2.QtCore.QCborStreamReader.StringResultCode¶
This enum is returned by
readString()
andreadByteArray()
and is used to indicate what the status of the parsing is.Constant
Description
QCborStreamReader.EndOfString
The parsing for the string is complete, with no error.
QCborStreamReader.Ok
The function returned data; there was no error.
QCborStreamReader.Error
Parsing failed with an error.
- PySide2.QtCore.QCborStreamReader.addData(data)¶
- Parameters:
data –
PySide2.QtCore.QByteArray
Adds
data
to the CBOR stream and reparses the current element. This function is useful if the end of the data was previously reached while processing the stream, but now more data is available.
- PySide2.QtCore.QCborStreamReader.addData(data, len)
- Parameters:
data – str
len –
long long
- PySide2.QtCore.QCborStreamReader.addData(data, len)
- Parameters:
data –
quint8
len –
long long
- PySide2.QtCore.QCborStreamReader.clear()¶
Clears the decoder state and resets the input source data to an empty byte array. After this function is called,
QCborStreamReader
will be indicating an error parsing.Call
addData()
to add more data to be parsed.See also
- PySide2.QtCore.QCborStreamReader.containerDepth()¶
- Return type:
int
Returns the number of containers that this stream has entered with
enterContainer()
but not yet left.See also
- PySide2.QtCore.QCborStreamReader.currentOffset()¶
- Return type:
int
Returns the offset in the input stream of the item currently being decoded. The current offset is the number of decoded bytes so far only if the source data is a
QByteArray
or it is aQIODevice
that was positioned at its beginning when decoding started.
- PySide2.QtCore.QCborStreamReader.currentStringChunkSize()¶
- Return type:
long long
Returns the size of the current text or byte string chunk. If the CBOR stream contains a non-chunked string (that is, if
isLengthKnown()
returnstrue
), this function returns the size of the entire string, the same aslength()
.This function is useful to pre-allocate the buffer whose pointer can be passed to
readStringChunk()
later.See also
readString()
readByteArray()
readStringChunk()
- PySide2.QtCore.QCborStreamReader.device()¶
- Return type:
Returns the
QIODevice
that was set with eithersetDevice()
or theQCborStreamReader
constructor. If this object was reading from aQByteArray
, this function returns nullptr instead.See also
- PySide2.QtCore.QCborStreamReader.enterContainer()¶
- Return type:
bool
Enters the array or map that is the current item and prepares for iterating the elements contained in the container. Returns true if entering the container succeeded, false otherwise (usually, a parsing error). Each call to must be paired with a call to
leaveContainer()
.This function may only be called if the current item is an array or a map (that is, if
isArray()
,isMap()
orisContainer()
is true). Calling it in any other condition is an error.See also
- PySide2.QtCore.QCborStreamReader.hasNext()¶
- Return type:
bool
Returns true if there are more items to be decoded in the current container or false of we’ve reached its end. If we’re parsing the root element, returning false indicates the parsing is complete; otherwise, if the container depth is non-zero, then the outer code needs to call
leaveContainer()
.
- PySide2.QtCore.QCborStreamReader.isArray()¶
- Return type:
bool
Returns true if the type of the current element is an array (that is, if
type()
returnsArray
). If this function returns true, you may callenterContainer()
to begin parsing that container.When the current element is an array, you may also call
isLengthKnown()
to find out if the array’s size is explicit in the CBOR stream. If it is, that size can be obtained by callinglength()
.The following example pre-allocates a
QVariantList
given the array’s size for more efficient decoding:QVariantList populateFromCbor(QCborStreamReader &reader) { QVariantList list; if (reader.isLengthKnown()) list.reserve(reader.length()); reader.enterContainer(); while (reader.lastError() == QCborError::NoError && reader.hasNext()) list.append(readOneElement(reader)); if (reader.lastError() == QCborError::NoError) reader.leaveContainer(); }
Note
The code above does not validate that the length is a sensible value. If the input stream reports that the length is 1 billion elements, the above function will try to allocate some 16 GB or more of RAM, which can lead to a crash.
- PySide2.QtCore.QCborStreamReader.isBool()¶
- Return type:
bool
Returns true if the current element is a boolean value (
true
orfalse
), false if it is anything else. If this function returns true, you may calltoBool()
to retrieve the value of the boolean. You may also calltoSimpleType()
and compare to either QCborSimpleValue::True or QCborSimpleValue::False.
- PySide2.QtCore.QCborStreamReader.isByteArray()¶
- Return type:
bool
Returns true if the type of the current element is a byte array (that is, if
type()
returnsByteArray
). If this function returns true, you may callreadByteArray()
to read that data.See also
- PySide2.QtCore.QCborStreamReader.isContainer()¶
- Return type:
bool
Returns true if the current element is a container (that is, an array or a map), false if it is anything else. If the current element is a container, the
isLengthKnown()
function may be used to find out if the container’s size is explicit in the stream and, if so,length()
can be used to get that size.More importantly, for a container, the
enterContainer()
function is available to begin iterating through the elements contained therein.
- PySide2.QtCore.QCborStreamReader.isDouble()¶
- Return type:
bool
Returns true if the type of the current element is an IEEE 754 double-precision floating point (that is, if
type()
returnsDouble
). If this function returns true, you may calltoDouble()
to read that data.See also
- PySide2.QtCore.QCborStreamReader.isFalse()¶
- Return type:
bool
Returns true if the current element is the
false
value, false if it is anything else.
- PySide2.QtCore.QCborStreamReader.isFloat()¶
- Return type:
bool
Returns true if the type of the current element is an IEEE 754 single-precision floating point (that is, if
type()
returnsFloat
). If this function returns true, you may calltoFloat()
to read that data.See also
- PySide2.QtCore.QCborStreamReader.isFloat16()¶
- Return type:
bool
Returns true if the type of the current element is an IEEE 754 half-precision floating point (that is, if
type()
returnsFloat16
). If this function returns true, you may calltoFloat16()
to read that data.See also
type()
toFloat16()
isFloat()
isDouble()
- PySide2.QtCore.QCborStreamReader.isInteger()¶
- Return type:
bool
Returns true if the type of the current element is either an unsigned integer or a negative one (that is, if
type()
returnsUnsignedInteger
orNegativeInteger
). If this function returns true, you may calltoInteger()
to read that value.See also
type()
toInteger()
toUnsignedInteger()
toNegativeInteger()
isUnsignedInteger()
isNegativeInteger()
- PySide2.QtCore.QCborStreamReader.isInvalid()¶
- Return type:
bool
Returns true if the current element is invalid, false otherwise. The current element may be invalid if there was a decoding error or we’ve just parsed the last element in an array or map.
Note
This function is not to be confused with
isNull()
. Null is a normal CBOR type that must be handled by the application.
- PySide2.QtCore.QCborStreamReader.isLengthKnown()¶
- Return type:
bool
Returns true if the length of the current array, map, byte array or string is known (explicit in the CBOR stream), false otherwise. This function should only be called if the element is one of those.
If the length is known, it may be obtained by calling
length()
.If the length of a map or an array is not known, it is implied by the number of elements present in the stream.
QCborStreamReader
has no API to calculate the length in that condition.Strings and byte arrays may also have indeterminate length (that is, they may be transmitted in multiple chunks). Those cannot currently be created with
QCborStreamWriter
, but they could be with other encoders, soQCborStreamReader
supports them.See also
- PySide2.QtCore.QCborStreamReader.isMap()¶
- Return type:
bool
Returns true if the type of the current element is a map (that is, if
type()
returnsMap
). If this function returns true, you may callenterContainer()
to begin parsing that container.When the current element is a map, you may also call
isLengthKnown()
to find out if the map’s size is explicit in the CBOR stream. If it is, that size can be obtained by callinglength()
.The following example pre-allocates a
QVariantMap
given the map’s size for more efficient decoding:QVariantMap populateFromCbor(QCborStreamReader &reader) { QVariantMap map; if (reader.isLengthKnown()) map.reserve(reader.length()); reader.enterContainer(); while (reader.lastError() == QCborError::NoError && reader.hasNext()) { QString key = readElementAsString(reader); map.insert(key, readOneElement(reader)); } if (reader.lastError() == QCborError::NoError) reader.leaveContainer(); }
The example above uses a function called
readElementAsString
to read the map’s keys and obtain a string. That is because CBOR maps may contain any type as keys, not just strings. User code needs to either perform this conversion, reject non-string keys, or instead use a different container besidesQVariantMap
andQVariantHash
. For example, if the map is expected to contain integer keys, which is recommended as it reduces stream size and parsing, the correct container would be\l{QMap}<int, QVariant>
or\l{QHash}<int, QVariant>
.Note
The code above does not validate that the length is a sensible value. If the input stream reports that the length is 1 billion elements, the above function will try to allocate some 24 GB or more of RAM, which can lead to a crash.
- PySide2.QtCore.QCborStreamReader.isNegativeInteger()¶
- Return type:
bool
Returns true if the type of the current element is a negative integer (that is if
type()
returnsNegativeInteger
). If this function returns true, you may calltoNegativeInteger()
ortoInteger()
to read that value.See also
type()
toNegativeInteger()
toInteger()
isInteger()
isUnsignedInteger()
- PySide2.QtCore.QCborStreamReader.isNull()¶
- Return type:
bool
Returns true if the current element is the
null
value, false if it is anything else. Null values may be used to indicate the absence of some optional data.Note
This function is not the opposite of
isValid()
. A Null value is a valid CBOR value.See also
- PySide2.QtCore.QCborStreamReader.isSimpleType()¶
- Return type:
bool
Returns true if the type of the current element is any CBOR simple type, including a boolean value (true and false) as well as null and undefined. To find out which simple type this is, call
toSimpleType()
. Alternatively, to test for one specific simple type, call the overload that takes aQCborSimpleType
parameter.CBOR simple types are types that do not carry extra value. There are 255 possibilities, but there are currently only four values that have defined meaning. Code is not expected to cope with unknown simple types and may simply discard the stream as invalid if it finds an unknown one.
See also
QCborSimpleType
type()
isSimpleType(QCborSimpleType)
toSimpleType()
- PySide2.QtCore.QCborStreamReader.isSimpleType(st)
- Parameters:
st –
QCborSimpleType
- Return type:
bool
Returns true if the type of the current element is the simple type
st
, false otherwise. If this function returns true, thentoSimpleType()
will returnst
.CBOR simple types are types that do not carry extra value. There are 255 possibilities, but there are currently only four values that have defined meaning. Code is not expected to cope with unknown simple types and may simply discard the stream as invalid if it finds an unknown one.
See also
QCborSimpleType
type()
isSimpleType()
toSimpleType()
- PySide2.QtCore.QCborStreamReader.isString()¶
- Return type:
bool
Returns true if the type of the current element is a text string (that is, if
type()
returnsString
). If this function returns true, you may callreadString()
to read that data.See also
- PySide2.QtCore.QCborStreamReader.isTag()¶
- Return type:
bool
Returns true if the type of the current element is a CBOR tag (that is, if
type()
returnsTag
). If this function returns true, you may calltoTag()
to read that data.See also
type()
toTag()
- PySide2.QtCore.QCborStreamReader.isTrue()¶
- Return type:
bool
Returns true if the current element is the
true
value, false if it is anything else.
- PySide2.QtCore.QCborStreamReader.isUndefined()¶
- Return type:
bool
Returns true if the current element is the
undefined
value, false if it is anything else. Undefined values may be encoded to indicate that some conversion failed or was not possible when creating the stream.QCborStreamReader
never performs any replacement and this function will only return true if the stream contains an explicit undefined value.See also
- PySide2.QtCore.QCborStreamReader.isUnsignedInteger()¶
- Return type:
bool
Returns true if the type of the current element is an unsigned integer (that is if
type()
returnsUnsignedInteger
). If this function returns true, you may calltoUnsignedInteger()
ortoInteger()
to read that value.
- PySide2.QtCore.QCborStreamReader.isValid()¶
- Return type:
bool
Returns true if the current element is valid, false otherwise. The current element may be invalid if there was a decoding error or we’ve just parsed the last element in an array or map.
Note
This function is not the opposite of
isNull()
. Null is a normal CBOR type that must be handled by the application.See also
- PySide2.QtCore.QCborStreamReader.lastError()¶
- Return type:
Returns the last error in decoding the stream, if any. If no error was encountered, this returns an
NoError
.See also
- PySide2.QtCore.QCborStreamReader.leaveContainer()¶
- Return type:
bool
Leaves the array or map whose items were being processed and positions the decoder at the next item after the end of the container. Returns true if leaving the container succeeded, false otherwise (usually, a parsing error). Each call to
enterContainer()
must be paired with a call to .This function may only be called if
hasNext()
has returned false andcontainerDepth()
is not zero. Calling it in any other condition is an error.
- PySide2.QtCore.QCborStreamReader.length()¶
- Return type:
int
Returns the length of the string or byte array, or the number of items in an array or the number, of item pairs in a map, if known. This function must not be called if the length is unknown (that is, if
isLengthKnown()
returned false). It is an error to do that and it will causeQCborStreamReader
to stop parsing the input stream.See also
- PySide2.QtCore.QCborStreamReader.next([maxRecursion=10000])¶
- Parameters:
maxRecursion – int
- Return type:
bool
Advance the CBOR stream decoding one element. You should usually call this function when parsing fixed-width basic elements (that is, integers, simple values, tags and floating point values). But this function can be called when the current item is a string, array or map too and it will skip over that entire element, including all contained elements.
This function returns true if advancing was successful, false otherwise. It may fail if the stream is corrupt, incomplete or if the nesting level of arrays and maps exceeds
maxRecursion
. Calling this function whenhasNext()
has returned false is also an error. If this function returns false,lastError()
will return the error code detailing what the failure was.See also
- PySide2.QtCore.QCborStreamReader.parentContainerType()¶
- Return type:
Returns either
Array
orMap
, indicating whether the container that contains the current item was an array or map, respectively. If we’re currently parsing the root element, this function returnsInvalid
.See also
- PySide2.QtCore.QCborStreamReader.readByteArray()¶
- Return type:
Decodes one byte array chunk from the CBOR string and returns it. This function is used for both regular and chunked contents, so the caller must always loop around calling this function, even if
isLengthKnown()
has is true. The typical use of this function is as follows:QBytearray decodeBytearray(QCborStreamReader &reader) { QBytearray result; auto r = reader.readBytearray(); while (r.code == QCborStreamReader::Ok) { result += r.data; r = reader.readByteArray(); } if (r.code == QCborStreamReader::Error) { // handle error condition result.clear(); } return result; }
This function does not perform any type conversions, including from integers or from strings. Therefore, it may only be called if
isByteArray()
is true; calling it in any other condition is an error.See also
readString()
isByteArray()
readStringChunk()
- PySide2.QtCore.QCborStreamReader.readString()¶
- Return type:
Decodes one string chunk from the CBOR string and returns it. This function is used for both regular and chunked string contents, so the caller must always loop around calling this function, even if
isLengthKnown()
has is true. The typical use of this function is as follows:QString decodeString(QCborStreamReader &reader) { QString result; auto r = reader.readString(); while (r.code == QCborStreamReader::Ok) { result += r.data; r = reader.readString(); } if (r.code == QCborStreamReader::Error) { // handle error condition result.clear(); } return result; }
This function does not perform any type conversions, including from integers or from byte arrays. Therefore, it may only be called if
isString()
returned true; calling it in any other condition is an error.See also
readByteArray()
isString()
readStringChunk()
- PySide2.QtCore.QCborStreamReader.reparse()¶
Reparses the current element. This function must be called when more data becomes available in the source
QIODevice
after parsing failed due to reaching the end of the input data before the end of the CBOR stream.When reading from QByteArray(), the
addData()
function automatically calls this function. Calling it when the reading had not failed is a no-op.
- PySide2.QtCore.QCborStreamReader.reset()¶
Resets the source back to the beginning and clears the decoder state. If the source data was a
QByteArray
,QCborStreamReader
will restart from the beginning of the array.If the source data is a
QIODevice
, this function will callreset()
, which will seek to byte position 0. If the CBOR stream is not found at the beginning of the device (e.g., beginning of a file), then this function will likely do the wrong thing. Instead, position theQIODevice
to the right offset and callsetDevice()
.See also
- PySide2.QtCore.QCborStreamReader.setDevice(device)¶
- Parameters:
device –
PySide2.QtCore.QIODevice
Sets the source of data to
device
, resetting the decoder to its initial state.See also
- PySide2.QtCore.QCborStreamReader.toBool()¶
- Return type:
bool
Returns the boolean value of the current element.
This function does not perform any type conversions, including from integer. Therefore, it may only be called if
isTrue()
,isFalse()
orisBool()
returned true; calling it in any other condition is an error.See also
- PySide2.QtCore.QCborStreamReader.toDouble()¶
- Return type:
double
Returns the 64-bit double-precision floating point value of the current element.
This function does not perform any type conversions, including from other floating point types or from integer values. Therefore, it may only be called if
isDouble()
is true; calling it in any other condition is an error.See also
isDouble()
toFloat16()
toFloat()
- PySide2.QtCore.QCborStreamReader.toFloat()¶
- Return type:
float
Returns the 32-bit single-precision floating point value of the current element.
This function does not perform any type conversions, including from other floating point types or from integer values. Therefore, it may only be called if
isFloat()
is true; calling it in any other condition is an error.See also
isFloat()
toFloat16()
toDouble()
- PySide2.QtCore.QCborStreamReader.toInteger()¶
- Return type:
int
Returns the integer value of the current element, be it negative, positive or zero. If the value is larger than 2 63 - 1 or smaller than -2 63 , the returned value will overflow and will have an incorrect sign. If handling those values is required, use
toUnsignedInteger()
ortoNegativeInteger()
instead.This function does not perform any type conversions, including from boolean or CBOR tag. Therefore, it may only be called if
isInteger()
is true; calling it in any other condition is an error.See also
isInteger()
toUnsignedInteger()
toNegativeInteger()
- PySide2.QtCore.QCborStreamReader.toSimpleType()¶
- Return type:
QCborSimpleType
Returns value of the current simple type.
This function does not perform any type conversions, including from integer. Therefore, it may only be called if
isSimpleType()
is true; calling it in any other condition is an error.
- PySide2.QtCore.QCborStreamReader.toUnsignedInteger()¶
- Return type:
int
Returns the unsigned integer value of the current element.
This function does not perform any type conversions, including from boolean or CBOR tag. Therefore, it may only be called if
isUnsignedInteger()
is true; calling it in any other condition is an error.This function may be used to obtain numbers beyond the range of the return type of
toInteger()
.
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