QrCodeGenerator

Extension methods for the class.

Appends the specified number bits of the specified value to this bit array. The least significant bits of the specified value are added. They are appended in reverse order, from the most significant to the least significant one, i.e. bits 0 to len-1 are appended in the order len-1, len-2 ... 1, 0. Requires 0 ≤ len ≤ 31, and 0 ≤ val < 2^len.

The BitArray instance that this method extends. The value to append. The number of low-order bits in the value to append. Value or number of bits is out of range.

Appends the content of the specified bit array to the end of this array.

The BitArray instance that this method extends. The bit array to append If bitArray is null.

The exception that is thrown when the supplied data does not fit in the QR code.

Ways to handle this exception include:

• Decrease the error correction level (if it was greater than )
• Increase the maxVersion argument (if it was less than ). This advice applies to the advanced factory functions and only. Other factory functions automatically try all versions up to .
• Split the text into several segments and encode them using different encoding modes (see .)
• Make the text or binary data shorter.
• Change the text to fit the character set of a particular segment mode (e.g. alphanumeric).
• Reject the data and notify the caller/user.

Initializes a new instance of the class.

The message that describes the error.

Helper functions to check for valid arguments.

Ensures that the specified argument is not null. Throws a exception if the argument is null.

The type of the argument. The argument to check. Argument passed to function. The specified argument is null.

Represents a QR code containing text or binary data. Instances of this class represent an immutable square grid of dark and light pixels (called modules by the QR code specification). Static factory methods are provided to create QR codes from text or binary data. Some of the methods provide detailed control about the encoding parameters such a QR code size (called version by the standard), error correction level and mask. QR codes are a type of two-dimensional barcodes, invented by Denso Wave and described in the ISO/IEC 18004 standard. This class covers the QR Code Model 2 specification, supporting all versions (sizes) from 1 to 40, all 4 error correction levels, and 4 character encoding modes.

To create a QR code instance:

• High level: Take the payload data and call or .
• Mid level: Custom-make a list of instances and call
• Low level: Custom-make an array of data codeword bytes (including segment headers and final padding, excluding error correction codewords), supply the appropriate version number, and call the .

Creates a QR code representing the specified text using the specified error correction level. As a conservative upper bound, this function is guaranteed to succeed for strings with up to 738 Unicode code points (not UTF-16 code units) if the low error correction level is used. The smallest possible QR code version (size) is automatically chosen. The resulting ECC level will be higher than the one specified if it can be achieved without increasing the size (version).

The text to be encoded. The full range of Unicode characters may be used. The minimum error correction level to use. The created QR code instance representing the specified text. or is null. The text is too long to fit in the largest QR code size (version) at the specified error correction level.

Creates a QR code representing the specified binary data using the specified error correction level. This function encodes the data in the binary segment mode. The maximum number of bytes allowed is 2953. The smallest possible QR code version is automatically chosen. The resulting ECC level will be higher than the one specified if it can be achieved without increasing the size (version).

The binary data to encode. The minimum error correction level to use. The created QR code representing the specified data. or is null. The specified data is too long to fit in the largest QR code size (version) at the specified error correction level.

Creates a QR code representing the specified segments with the specified encoding parameters. The smallest possible QR code version (size) is used. The range of versions can be restricted by the and parameters. If is true, the resulting ECC level will be higher than the one specified if it can be achieved without increasing the size (version). The QR code mask is usually automatically chosen. It can be explicitly set with the parameter by using a value between 0 to 7 (inclusive). -1 is for automatic mode (which may be slow). This function allows the user to create a custom sequence of segments that switches between modes (such as alphanumeric and byte) to encode text in less space and gives full control over all encoding parameters.

This is a mid-level API; the high-level APIs are and . The segments to encode. The minimal or fixed error correction level to use . The minimum version (size) of the QR code (between 1 and 40). The maximum version (size) of the QR code (between 1 and 40). The mask number to use (between 0 and 7), or -1 for automatic mask selection. If true the ECC level wil be increased if it can be achieved without increasing the size (version). The created QR code representing the segments. , any list element, or is null. 1 ≤ minVersion ≤ maxVersion ≤ 40 or -1 ≤ mask ≤ 7 is violated. The segments are too long to fit in the largest QR code size (version) at the specified error correction level.

The version (size) of this QR code (between 1 for the smallest and 40 for the biggest).

The QR code version (size).

The width and height of this QR code, in modules (pixels). The size is a value between 21 and 177. This is equal to version × 4 + 17.

The QR code size.

The error correction level used for this QR code.

The error correction level.

The index of the mask pattern used fort this QR code (between 0 and 7). Even if a QR code is created with automatic mask selection (mask = 1), this property returns the effective mask used.

The mask pattern index.

Constructs a QR code with the specified version number, error correction level, data codeword bytes, and mask number.

This is a low-level API that most users should not use directly. A mid-level API is the function. The version (size) to use (between 1 to 40). The error correction level to use. The bytes representing segments to encode (without ECC). The mask pattern to use (either -1 for automatic selection, or a value from 0 to 7 for fixed choice). or is null. The version or mask value is out of range, or the data has an invalid length for the specified version and error correction level.

Gets the color of the module (pixel) at the specified coordinates. The top left corner has the coordinates (x=0, y=0). x-coordinates extend from left to right, y-coordinates extend from top to bottom. If coordinates outside the bounds of this QR code are specified, light (false) is returned.

The x coordinate. The y coordinate. The color of the specified module: true for dark modules and false for light modules (or if the coordinates are outside the bounds).

Creates an SVG image of this QR code. The images uses Unix newlines (\n), regardless of the platform.

The border width, as a factor of the module (QR code pixel) size The SVG image as a string.

Creates an SVG image of this QR code. The images uses Unix newlines (\n), regardless of the platform. Colors are specified using CSS color data type. Examples of valid values are "#339966", "fuchsia", "rgba(137, 23, 89, 0.3)".

The border width, as a factor of the module (QR code pixel) size The foreground color. The background color.

Creates a graphics path of this QR code valid in SVG or XAML. The graphics path uses a coordinate system where each module is 1 unit wide and tall, and the top left module is offset vertically and horizontally by border units. Note that a border width other than 0 only make sense if the bounding box of the QR code is explicitly set by the graphics using this path. If the bounding box of this path is automatically derived, at least the right and bottom border will be missing. The path will look like this: M3,3h7v1h-7z M12,3h1v4h-1z ... M70,71h1v1h-1z. It is valid for SVG (<path d="M3,3h..." />) and for XAML (<Path Data="M3,3h..." />). For programmatic geometry creation in WPF see Geometry.Parse(String).

The border width, as a factor of the module (QR code pixel) size The graphics path Thrown if border is negative

Creates a bitmap in the BMP format. The bitmap uses 1 bit per pixel and a color table with 2 entries. Color values can be created with .

The border width, as a factor of the module (QR code pixel) size. The width and height, in pixels, of each module. The foreground color (dark modules), in RGB value (little endian). The background color (light modules), in RGB value (little endian). Bitmap data Thrown if is negative, is less than 1 or the resulting image is wider than 32,768 pixels.

Creates bitmap in the BMP format data using black for dark modules and white for light modules. The bitmap uses 1 bit per pixel and a color table with 2 entries.

The border width, as a factor of the module (QR code pixel) size. The width and height, in pixels, of each module. Bitmap data Thrown if is negative, is less than 1 or the resulting image is wider than 32,768 pixels.

Creates an RGB color value in little endian format.

Red component. Green component. Blue component. RGB color value

The minimum version (size) supported in the QR Code Model 2 standard – namely 1.

The minimum version.

The maximum version (size) supported in the QR Code Model 2 standard – namely 40.

The maximum version.

Error correction level in QR code symbol.

Low error correction level. The QR code can tolerate about 7% erroneous codewords.

Low error correction level.

Medium error correction level. The QR code can tolerate about 15% erroneous codewords.

Medium error correction level.

Quartile error correction level. The QR code can tolerate about 25% erroneous codewords.

Quartile error correction level.

High error correction level. The QR code can tolerate about 30% erroneous codewords.

High error correction level.

Ordinal number of error correction level (in the range 0 to 3).

Higher number represent a higher amount of error tolerance. Ordinal number.

Represents a segment of character/binary/control data in a QR code symbol.

The easiest way to deal with QR code segments is to call or , and not to use instances of this class directly. The mid-level way is to take the payload data and call a static factory function such as . The low-level way is to custom-make the bit array and call the constructor with appropriate values. This segment class imposes no length restrictions, but QR codes have restrictions. Even in the most favorable conditions, a QR code can only hold 7089 characters of data. Any segment longer than this is meaningless for the purpose of generating QR codes. This class can represent kanji mode segments, but provides no help in encoding them - see for full kanji support. Instances of this class are immutable.

Creates a segment representing the specified binary data encoded in byte mode. All input byte arrays are acceptable. Any text string can be converted to UTF-8 bytes (using Encoding.UTF8.GetBytes(str)) and encoded as a byte mode segment.

The binary data to encode. The created segment containing the specified data. data is null.

Creates a segment representing the specified string of decimal digits. The segment is encoded in numeric mode.

The text to encode, consisting of digits from 0 to 9 only. The created segment containing the text. digits is null. digits contains non-digit characters

Creates a segment representing the specified text string. The segment is encoded in alphanumeric mode. Allowed characters are: 0 to 9, A to Z (uppercase only), space, dollar, percent, asterisk, plus, hyphen, period, slash, colon.

The text to encode, consisting of allowed characters only. The created segment containing the text. text is null. text contains non-encodable characters.

Creates a list of zero or more segments representing the specified text string. The text may contain the full range of Unicode characters. The result may multiple segments with various encoding modes in order to minimize the length of the bit stream.

The text to be encoded. The created mutable list of segments representing the specified text. text is null. The current implementation does not use multiple segments.

Creates a segment representing an Extended Channel Interpretation (ECI) designator with the specified assignment value.

The ECI assignment number (see the AIM ECI specification). The created segment containing the data. assignValis outside the range [0, 10⁶).

Tests whether the specified string can be encoded as a segment in numeric mode. A string is encodable iff each character is in the range "0" to "9".

the string to test for encodability (not null) true iff each character is in the range "0" to "9". if the string is null

Tests whether the specified string can be encoded as a segment in alphanumeric mode. A string is encodable iff each character is in the range "0" to "9", "A" to "Z" (uppercase only), space, dollar, percent, asterisk, plus, hyphen, period, slash, colon.

the string to test for encodability (not null) true iff each character is in the alphanumeric mode character set. if the string is null

The encoding mode of this segment.

Encoding mode.

The length of this segment's unencoded data. Measured in characters for numeric/alphanumeric/kanji mode, bytes for byte mode, and 0 for ECI mode. Different from the data's bit length.

Length of the segment's unencoded data.

Initializes a QR code segment with the specified attributes and data. The character count must agree with the mode and the bit array length, but the constraint isn't checked. The specified bit array is cloned.

The segment mode used to encode this segment. The data length in characters or bytes (depending on the segment mode). The data bits. or is null. is negative.

Returns a copy of this segment's data bits.

A copy of the data bits.

Segment encoding mode. Describes how text or binary data is encoded into bits.

Numeric encoding mode.

Numeric encoding mode.

Alphanumeric encoding mode.

Alphanumeric encoding mode.

Byte encoding mode.

Byte encoding mode.

Kanji encoding mode.

Kanji encoding mode.

ECI encoding mode.

ECI encoding mode.

Mode indicator value. 4 bit value in the QR segment header indicating the encoding mode.

Mode indicator value

Array of character count bit length. Number of bits for character count in QR segment header. The three array values apply to versions 0 to 9, 10 to 26 and 27 to 40 respectively. All array values are in the range [0, 16].

Array of character count bit length

Returns the bit length of the character count in the QR segment header for the specified QR code version. The result is in the range [0, 16].

the QR code version (between 1 and 40)

Advanced methods for encoding QR codes using Kanji mode or using multiple segments with different encodings.

Creates a list of zero or more segments to represent the specified text string. The resulting list optimally minimizes the total encoded bit length, subjected to the constraints of the specified error correction level, minimum and maximum version number. This function potentially uses all four text encoding modes: numeric, alphanumeric, byte (UTF-8), and Kanji. It is a more sophisticated but slower replacement for . The text to be encoded can contain the full set of Unicode characters (code points).

The text to be encoded. The error correction level to use. The minimum version (size) of the QR code (between 1 and 40). The maximum version (size) of the QR code (between 1 and 40). The created mutable list of segments encoding the specified text with a minimal bit length. or is null. 1 ≤ minVersion ≤ maxVersion ≤ 40 is violated. The text is too long to fit into the QR code with the given encoding parameters.

Creates a segment encoding the specified text in Kanji mode. Broadly speaking, the set of encodable characters are Kanji used in Japan, Hiragana, Katakana, East Asian punctuation, full-width ASCII, Greek, and Cyrillic. Examples of non-encodable characters include ordinary ASCII, half-width Katakana, more extensive Chinese Hanzi.

The text to encoding, containing only characters allowed by the Kanji encoding. The created segment representing the specified text. is null. contains non-encodable characters.

Tests whether the specified string can be encoded as a segment in Kanji mode. Broadly speaking, the set of encodable characters are Kanji used in Japan, Hiragana, Katakana, East Asian punctuation, full-width ASCII, Greek, and Cyrillic. Examples of non-encodable characters include ordinary ASCII, half-width Katakana, more extensive Chinese Hanzi.

The text to test for encodability. true iff each character is in the Kanji mode character set. is null.

Computes the Reed-Solomon error correction codewords for a sequence of data codewords at a given degree. Instances are immutable, and the state only depends on the degree. This class is useful because all data blocks in a QR code share the same the divisor polynomial.

Initializes a new Reed-Solomon ECC generator for the specified degree.

This could be implemented as a lookup table over all possible parameter values, instead of as an algorithm. The divisor polynomial degree (between 1 and 255). degree < 1 or degree > 255

Computes the Reed-Solomon error correction codewords for the specified sequence of data codewords. This method does not alter this object's state (as it is immutable).

The sequence of data codewords. The Reed-Solomon error correction codewords, as a byte array. If data is null.