Formats React Native Reference Documentation
Formats
Current Version: 11.7.0
Markdown version of this page for AI tools (v 11.7.0) · all AI docs
Chilkat.Formats
Versions 1–40, error-correction levels L/M/Q/H, automatic or explicit version and mask, numeric/alphanumeric/byte modes, ECI, structured append. Integer-pixel modules, px/mm/in/pt units with DPI, quiet zone, padding, rotation, colors with opacity, caption text, size limits with shrink-to-fit. Returned inline as base64 or SVG text, or written to files (numbered file sets for structured append). Optional module bit-matrix and reusable definition.
See the Barcode / QR Code Generation Overview
for the complete documentation with examples and sample images.
A collection of data-format operations, starting with barcode and QR code generation.
Chilkat.Formats is not string, number or date display formatting. It groups operations on
well-defined data formats behind a small number of JSON-driven methods, so the class can grow by adding a
method per format family without adding a public class for each feature. Introduced in v11.7.0 with the
barcode feature methods Barcode and QrCode.
QR Code generation
Precise rendering
PNG or SVG output
Measure and validate
measure reports exact geometry without rendering; validate checks a request; capabilities describes what the build supports.method(op, jsonIn, jsonOut). Requests are
checked strictly (unknown options are rejected, not ignored) and every failure has a stable error code with the
JSON Pointer of the offending member.
Object Creation
// npm install @chilkat/react-native react-native-nitro-modules
// (React Native 0.76+ with the New Architecture; then `pod install` for iOS. The Chilkat
// native library is downloaded and verified during the native build -- see the package README.)
import { Chilkat, Formats } from '@chilkat/react-native'
// Once per app start, before any other Chilkat call:
Chilkat.unlockBundle('Anything for 30-day trial') // shorthand for new Global().unlockBundle(..)
const formats = new Formats()
// ... the native object is released when `formats` is garbage collected, or now with formats.dispose()Creates the underlying native Chilkat object. Formats is a Nitro Module HybridObject: use it from the JavaScript thread only (it cannot be passed to a Worklet or another runtime). Every member is synchronous and blocks the JavaScript thread until Chilkat returns; a method that can take a while also exists as a ...Async twin returning a Promise, which runs the same call on a native worker thread so the UI keeps rendering. While such a call is pending, every other call on this object throws, except abort() and assigning onPercentDone / onProgressInfo.
Releases the native object immediately instead of waiting for garbage collection (useful for a large BinData or an open socket). Calling it more than once is harmless; any other use of the object afterwards throws. An object with a pending ...Async call cannot be disposed until the promise settles.
Errors
A method that can fail throws a plain Error: 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 error's message is "Class.method(...): reason", where the reason is the last informative line of the object's lastErrorText, which holds the full Chilkat log of the failed call. A ...Async twin rejects its promise with the same Error instead of throwing. Properties never throw, and methods that answer a question (has..., is..., ...) return a plain boolean.
try {
formats.someMethod(...)
} catch (e) {
console.log((e as Error).message) // Formats.someMethod(...): <reason>
console.log(formats.lastErrorText) // the full Chilkat log of the failed call
}
// The same call without blocking the JavaScript thread:
try {
await formats.someMethodAsync(...)
} catch (e) {
console.log((e as Error).message) // Formats.someMethodAsync: <reason>
}Properties
DebugLogFilePath
debugLogFilePath: string
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.
LastErrorHtml
readonly lastErrorHtml: string
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
readonly lastErrorText: string
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
readonly lastErrorXml: string
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
lastMethodSuccess: boolean
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.
VerboseLogging
verboseLogging: boolean
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
readonly version: string
Methods
Barcode
Runs one barcode operation and returns the result as JSON. op is the operation: "generate" (encode the payload, lay out the symbol and render a PNG or SVG), "measure" (encode and lay out only, reporting the exact geometry and whether the symbol fits), "validate" (examine a request's definition, capacity or layout) or "capabilities" (describe the symbologies, operations, formats and limits this build implements). jsonIn is the request: it names the symbology (currently "qr"), the payload (text or base64 binary) and optional encoding, render, output and limits groups. jsonOut is replaced with the response. Every response carries errors[] and warnings[]; a successful "generate" also returns symbols[] (the encoding actually selected), measurements[] (pixel geometry) and outputs[] (the image as base64 or SVG text, or the path of the file written).
Returns true when the operation completed successfully. Returns false when the request was rejected or execution failed; errors[0] then holds a stable code, the JSON Pointer path of the offending request member and a message.
The request and response vocabulary (payload types, QR version, error correction, mask, ECI, structured append, module size and physical units, quiet zone, rotation, colors, captions, PNG/SVG output, file writing, limits and error codes) is documented in full, with examples and sample images, at the links below.
Returns normally on success; throws an Error on failure.
QrCode
The same as Barcode with the symbology defaulting to "qr", so the smallest request is { "payload": { "text": "..." } }. op is the operation ("generate", "measure", "validate" or "capabilities"), jsonIn the request and jsonOut the response. Identical requests to QrCode and Barcode produce identical results; a request naming a symbology outside the QR family is rejected.
Generates QR Code (Model 2) symbols in versions 1-40 with error-correction levels L, M, Q and H, automatic or explicit version and mask selection, numeric, alphanumeric and byte modes, optional ECI, and structured append of up to 16 symbols. Output is PNG or SVG, returned inline (base64 or SVG text) and/or written to files.
Returns true when the operation completed successfully, otherwise false with the reason in errors[0] of jsonOut (code, JSON Pointer path and message). See the links below for the complete documentation of every option, with examples and sample images.
Returns normally on success; throws an Error on failure.