Asn Dart Reference Documentation
CkAsn
Current Version: 11.6.1
Chilkat.Asn
Load ASN.1 from binary DER bytes, encoded text such as Base64 or hex,
files, or existing
Read the item tag, tag value, constructed/primitive state, sub-item
count, string content, boolean value, or integer value.
Append constructed
Add booleans, integers, big integers, bit strings, octet strings, OIDs,
strings, times, null values, and encoded byte content.
Add context-specific primitive or constructed items when working with
ASN.1 formats that use tagged application-specific structures.
Convert ASN.1 to XML for inspection or editing, load ASN.1 back from XML,
and output the result as binary or encoded DER.
Load, inspect, build, edit, and encode ASN.1 structures in DER or XML form.
Chilkat.Asn represents an ASN.1 item and its optional child
items. It can load ASN.1 from binary DER, encoded DER strings, files, or
BinData; expose tags, tag values, primitive content, boolean
and integer values, and child counts; build constructed structures such as
SEQUENCE and SET; append common primitive types
such as booleans, integers, big integers, bit strings, octets, OIDs, strings,
times, null values, and context-specific items; convert ASN.1 to XML; reload
from that XML form; and write the final structure back to DER.
Load DER data
BinData objects.
Inspect ASN.1 items
Build sequences and sets
SEQUENCE and SET items,
then add child ASN.1 values beneath them.
Append primitive values
Context-specific tags
DER and XML conversion
LoadBinary, LoadEncoded,
LoadBd, or LoadBinaryFile, inspect the tree with
Tag, Constructed, NumSubItems, and
GetSubItem, then extract primitive content or convert to XML
with AsnToXml. To create ASN.1, start with a constructed item,
append child values, and write the final DER with GetBinaryDer,
GetEncodedDer, WriteBd, or
WriteBinaryDer.
Object Creation
// pubspec.yaml:
// dependencies:
// chilkat: ^11.6.1
import 'package:chilkat/chilkat.dart';
// Once per process, before any other Chilkat call:
Chilkat.unlockBundle('Anything for 30-day trial'); // shorthand for CkGlobal().unlockBundle(..)
final asn = CkAsn();
// ... the native object is released when `asn` is garbage collected, or now with asn.dispose().Creates the underlying native Chilkat object. Use a CkAsn only from the isolate that created it: Chilkat objects cannot be sent between isolates. Every call is synchronous; in a Flutter app, run long operations (network, large files) inside Isolate.run, creating the Chilkat objects inside the isolate.
Releases the native object immediately instead of waiting for garbage collection (useful for a large CkBinData or an open socket). Calling it more than once is harmless; any other use of the object afterwards throws a StateError. isDisposed tells whether it has been called.
Errors
A method that can fail throws a ChilkatException: a method whose only outcome is success or failure returns void and throws on failure; a method producing a String or an object returns it and throws where Chilkat would have returned null. The exception carries the object's LastErrorText at the time of the failure (lastErrorText), the class and method names (className, methodName) and a one-line message. Properties never throw, and methods that answer a question (has..., is..., ...) return a plain bool.
try {
asn.someMethod(...);
} on ChilkatException catch (e) {
print(e); // CkAsn.someMethod failed: <reason>
print(e.lastErrorText); // the full Chilkat log of the failed call
}Properties
BoolValue
bool get boolValue
set boolValue(bool value)
The ASN.1 item's boolean value if it is a boolean item.
topConstructed
bool get constructed
true if this ASN.1 item is a constructed item. Sequence and Set items are constructed and can contain sub-items. All other tags (boolean, integer, octets, utf8String, etc.) are primitive (non-constructed).
ContentStr
String get contentStr
set contentStr(String value)
The ASN.1 item's content if it is an ASN.1 string type (such as Utf8String, BmpString, PrintableString, VisibleString, T61String, IA5String, NumericString, or UniversalString).
topDebugLogFilePath
String get debugLogFilePath
set debugLogFilePath(String value)
If set to a file path, this property logs the LastErrorText of each Chilkat method or property call to the specified file. This logging helps identify the context and history of Chilkat calls leading up to any crash or hang, aiding in debugging.
Enabling the VerboseLogging property provides more detailed information. This property is mainly used for debugging rare instances where a Chilkat method call causes a hang or crash, which should generally not happen.
Possible causes of hangs include:
- A timeout property set to 0, indicating an infinite timeout.
- A hang occurring within an event callback in the application code.
- An internal bug in the Chilkat code causing the hang.
IntValue
int get intValue
set intValue(int value)
The ASN.1 item's integer value if it is a small integer item.
topLastErrorHtml
String get lastErrorHtml
Provides HTML-formatted information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.
topLastErrorText
String get lastErrorText
Provides plain text information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.
LastErrorXml
String get lastErrorXml
Provides XML-formatted information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.
topLastMethodSuccess
bool get lastMethodSuccess
set lastMethodSuccess(bool value)
Indicates the success or failure of the most recent method call: true means success, false means failure. This property remains unchanged by property setters or getters. This method is present to address challenges in checking for null or Nothing returns in certain programming languages. Note: This property does not apply to methods that return integer values or to boolean-returning methods where the boolean does not indicate success or failure.
NumSubItems
int get numSubItems
The number of sub-items contained within this ASN.1 item. Only constructed items, such as Sequence and Set will contain sub-iitems. Primitive items such as OIDs, octet strings, integers, etc. will never contain sub-items.
topTag
String get tag
The ASN.1 item's tag as a descriptive string. Possible values are:
boolean integer bitString octets null oid utf8String relativeOid sequence set numericString printableString t61String ia5String utcTime bmpStringtop
TagValue
int get tagValue
The ASN.1 item's tag as a integer value. The integer values for possible tags are as follows:
boolean (1) integer (2) bitString (3) octets (4) null (5) oid (6) utf8String (12) relativeOid (13) sequence (16) set (17) numericString (18) printableString (19) t61String (20) ia5String (22) utcTime (23) bmpString (30)top
VerboseLogging
bool get verboseLogging
set verboseLogging(bool value)
If set to true, then the contents of LastErrorText (or LastErrorXml, or LastErrorHtml) may contain more verbose information. The default value is false. Verbose logging should only be used for debugging. The potentially large quantity of logged information may adversely affect peformance.
Version
String get version
Methods
AppendBigInt
Appends an ASN.1 integer, but one that is a big (huge) integer that is too large to be represented by an integer variable. The bytes composing the integer are passed in encoded string format (such as base64, hex, etc.). The byte order must be big-endian. The encoding may be any of the following encodings: Base64, Hex, Base58, modBase64, Base32, UU, QP (for quoted-printable), URL (for url-encoding), Q, B, url_oath, url_rfc1738, url_rfc2396, and url_rfc3986. The encoding name is case insensitive (for example, both Base64 and base64 are treated the same).
Returns normally on success; throws a ChilkatException on failure.
AppendBits
Appends an ASN.1 bit string to the caller's sub-items. The bytes containing the bits are passed in encoded string format (such as base64, hex, etc.). The byte order must be big-endian (MSB first). The encoding may be any of the following encodings: Base64, Hex, Base58, modBase64, Base32, UU, QP (for quoted-printable), URL (for url-encoding), Q, B, url_oath, url_rfc1738, url_rfc2396, and url_rfc3986. The encoding name is case insensitive (for example, both Base64 and base64 are treated the same).
Returns normally on success; throws a ChilkatException on failure.
AppendBool
Appends an ASN.1 boolean item to the caller's sub-items. Items may only be appended to constructed data types such as Sequence and Set.
Returns normally on success; throws a ChilkatException on failure.
AppendContextConstructed
Appends an ASN.1 context-specific constructed item to the caller's sub-items.
Returns normally on success; throws a ChilkatException on failure.
AppendContextPrimitive
Appends an ASN.1 context-specific primitive item to the caller's sub-items. The bytes are passed in encoded string format (such as base64, hex, etc.). The encoding may be any of the following encodings: Base64, Hex, Base58, modBase64, Base32, UU, QP (for quoted-printable), URL (for url-encoding), Q, B, url_oath, url_rfc1738, url_rfc2396, and url_rfc3986. The encoding name is case insensitive (for example, both Base64 and base64 are treated the same).
Returns normally on success; throws a ChilkatException on failure.
AppendInt
Appends an ASN.1 integer item to the caller's sub-items. Items may only be appended to constructed data types such as Sequence and Set.
Returns normally on success; throws a ChilkatException on failure.
AppendNull
Appends an ASN.1 null item to the caller's sub-items. Items may only be appended to constructed data types such as Sequence and Set.
Returns normally on success; throws a ChilkatException on failure.
AppendOctets
Appends an ASN.1 octet string to the caller's sub-items. The bytes are passed in encoded string format (such as base64, hex, etc.). The encoding may be any of the following encodings: Base64, Hex, Base58, modBase64, Base32, UU, QP (for quoted-printable), URL (for url-encoding), Q, B, url_oath, url_rfc1738, url_rfc2396, and url_rfc3986. The encoding name is case insensitive (for example, both Base64 and base64 are treated the same).
Returns normally on success; throws a ChilkatException on failure.
AppendOid
Appends an ASN.1 OID (object identifier) to the caller's sub-items. The OID is passed in string form, such as 1.2.840.113549.1.9.1.
Returns normally on success; throws a ChilkatException on failure.
AppendSequence
Appends an ASN.1 sequence item to the caller's sub-items.
Returns normally on success; throws a ChilkatException on failure.
AppendSequence2
Appends an ASN.1 sequence item to the caller's sub-items, and updates the internal reference to point to the newly appended sequence item.
Returns normally on success; throws a ChilkatException on failure.
AppendSequenceR
Appends an ASN.1 sequence item to the caller's sub-items, and returns the newly appended sequence item.
Throws a ChilkatException on failure (where the description says null is returned, the Dart method throws instead).
AppendSet
Appends an ASN.1 set item to the caller's sub-items.
Returns normally on success; throws a ChilkatException on failure.
AppendSet2
Appends an ASN.1 set item to the caller's sub-items, and updates the internal reference to point to the newly appended set item.
Returns normally on success; throws a ChilkatException on failure.
AppendSetR
Appends an ASN.1 set item to the caller's sub-items, and returns the newly appended set item.
Throws a ChilkatException on failure (where the description says null is returned, the Dart method throws instead).
AppendString
Appends a string item to the caller's sub-items. The strType specifies the type of string to be added. It may be utf8, ia5, t61, printable, visible, numeric, universal, or bmp. The value must conform to the ASN.1 restrictions imposed for a given string type. The utf8, bmp, and universal types have no restrictions on what characters are allowed. In general, unless a specific type of string is required, choose the utf8 type.
Returns normally on success; throws a ChilkatException on failure.
AppendTime
Appends a UTCTime item to the caller's sub-items. The timeFormat specifies the format of the dateTimeStr. It should be set to utc. (In the future, this method will be expanded to append GeneralizedTime items by using generalized for timeFormat.) To append the current date/time, set dateTimeStr equal to the empty string or the keyword now. Otherwise, the dateTimeStr should be in the UTC time format YYMMDDhhmm[ss]Z or YYMMDDhhmm[ss](+|-)hhmm.
Returns normally on success; throws a ChilkatException on failure.
AsnToXml
Converts ASN.1 to XML and returns the XML string.
Throws a ChilkatException on failure (where the description says null is returned, the Dart method throws instead).
DeleteSubItem
Discards the Nth sub-item. (The 1st sub-item is at index 0.)
Returns normally on success; throws a ChilkatException on failure.
GetEncodedContent
Returns the content of the ASN.1 item in encoded string form. The encoding may be any of the following encodings: Base64, Hex, Base58, modBase64, Base32, UU, QP (for quoted-printable), URL (for url-encoding), Q, B, url_oath, url_rfc1738, url_rfc2396, and url_rfc3986. The encoding name is case insensitive (for example, both Base64 and base64 are treated the same).
Throws a ChilkatException on failure (where the description says null is returned, the Dart method throws instead).
GetEncodedDer
Returns the binary DER in encoded string form. The encoding indicates the encoding and can be base64, hex, uu, quoted-printable, base32, or modbase64.
Throws a ChilkatException on failure (where the description says null is returned, the Dart method throws instead).
GetLastSubItem
Returns the last ASN.1 sub-item. This method can be called immediately after any Append* method to access the appended item.
Throws a ChilkatException on failure (where the description says null is returned, the Dart method throws instead).
GetSubItem
Returns the Nth ASN.1 sub-item. The 1st sub-item is at index 0.
Throws a ChilkatException on failure (where the description says null is returned, the Dart method throws instead).
LoadAsnXml
Loads ASN.1 from the XML representation (such as that created by the AsnToXml method).
Returns normally on success; throws a ChilkatException on failure.
LoadBd
Loads ASN.1 from the binary DER contained in bd.
Returns normally on success; throws a ChilkatException on failure.
LoadBinaryFile
Loads ASN.1 from a binary DER file.
Returns normally on success; throws a ChilkatException on failure.
LoadEncoded
Loads ASN.1 from an encoded string. The encoding can be base64, hex, uu, quoted-printable, base32, or modbase64.
Returns normally on success; throws a ChilkatException on failure.
SetEncodedContent
Sets the content of this primitive ASN.1 item. The encoding may be any of the following encodings: Base64, Hex, Base58, modBase64, Base32, UU, QP (for quoted-printable), URL (for url-encoding), Q, B, url_oath, url_rfc1738, url_rfc2396, and url_rfc3986. The encoding name is case insensitive (for example, both Base64 and base64 are treated the same).
Returns normally on success; throws a ChilkatException on failure.
WriteBd
Appends the ASN.1 in binary DER format to bd.
Returns normally on success; throws a ChilkatException on failure.
WriteBinaryDer
Writes the ASN.1 in binary DER form to a file.
Returns normally on success; throws a ChilkatException on failure.