API-Referenz zu node:util

Zu den gängigen Hilfsfunktionen in node:util gehören:

format, formatWithOptions, inspect und stripVTControlCharacters;
promisify, callbackify, inherits, deprecate und debuglog;
isDeepStrictEqual, parseArgs, parseEnv und styleText;
getSystemErrorName, getSystemErrorMessage und getSystemErrorMap;
getCallSites;
die globalen Konstruktoren TextEncoder und TextDecoder.

toUSVString() und die veraltete Hilfsfunktion log() sind vorhanden, werfen aber einen Implementierungsfehler.

Beispiele

const util = require("node:util");

util.inspect({ a: [1, 2] }); // "{ a: [ 1, 2 ] }"
util.format("%s:%d", "port", 8080); // "port:8080"
util.isDeepStrictEqual({ a: 1 }, { a: 1 }); // true

inspect() verarbeitet gängige Container, typisierte Arrays, Buffer, Funktionen, zirkuläre Referenzen, Promises und util.inspect.custom. Optionen wie depth, breakLength, compact und maxArrayLength sind verfügbar.

promisify() berücksichtigt util.promisify.custom.

util.types

Die Prädikatfamilie deckt gängige Arrays und Views, Daten, Maps, Sets, Fehler, Promises, Proxies, reguläre Ausdrücke, schwache Collections, geboxte Primitive, Funktionsarten, Iteratoren und Spezialisierungen typisierter Arrays ab. Nicht jedes Node-Prädikat ist vorhanden; prüfen Sie neuere Prädikate wie isCryptoKey vor dem Aufruf auf Existenz.

Siehe auch

Node.js-util-API

Reference

Status: Partial · 9 of 18 suite tests pass (50.0%) · since 1.1.0

Exports

Export	Kind	Status	Notes
`format()`	function	Full	Formats a string using printf-style substitution patterns (%s, %d, %o, etc.)
`formatWithOptions()`	function	Full	Like format(), but accepts an explicit util.inspect options object for the first argument
`inspect()`	function	Full	Returns a string representation of an object for debugging
`promisify()`	function	Full	Wraps a callback-based function so it returns a Promise
`inherits()`	function	Full	Sets up prototype inheritance between a constructor and a superclass
`isDeepStrictEqual()`	function	Full	Returns true if two values are deeply equal using the strict equality algorithm
`deprecate()`	function	Full	Wraps a function to emit a deprecation warning when called
`debuglog()`	function	Full	Returns a logging function that writes to stderr only if the NODE_DEBUG env variable includes section
`callbackify()`	function	Full	Wraps an async function (or a function that returns a Promise) so it follows the error-first callback…
`getSystemErrorName()`	function	Full	Returns the string name for a numeric error code (the errno value)
`getSystemErrorMessage()`	function	Full	Returns the string message for a numeric error code (the errno value)
`getSystemErrorMap()`	function	Full	Returns a Map of all system error codes to [name, message] pairs
`toUSVString()`	function	Full	Returns a string after replacing any lone surrogates with the Unicode replacement character U+FFFD
`stripVTControlCharacters()`	function	Full	Removes ANSI escape codes (including color and cursor movement) from a string
`styleText()`	function	Full	Formats text with ANSI styling for terminal output
`getCallSites()`	function	Full	Returns an array of call site objects representing the current call stack
`parseEnv()`	function	Full	Parses a .env file content string into a key-value object
`log()`	function	Full	Writes a formatted timestamp + message to stdout (similar to console.log but with a timestamp)
`types`	property	Full	Object with type-checking predicates (e.g. util.types.isDate, util.types.isMap)
`TextEncoder`	property	Full	The WHATWG TextEncoder class
`TextDecoder`	property	Full	The WHATWG TextDecoder class

Not implemented

convertProcessSignalToExitCode, debug, diff, isArray, setTraceSigInt, transferableAbortController, transferableAbortSignal.

Tests: node-api node:util: 9 pass, 8 fail, 1 error, 12 skipped. Failing: test-util-callbackify.js, test-util-format.js, test-util-getcallsites-preparestacktrace.js, test-util-getcallsites-sourcemap.js, test-util-inspect-getters-accessing-this.js, test-util-inspect-long-running.js, test-util-inspect-namespace.js, test-util-inspect-regexp.js, and 1 more.