Hashtable React Native Reference Documentation

Hashtable

Current Version: 11.6.1

Chilkat.Hashtable

Store, look up, remove, enumerate, import, and serialize key/value pairs.

Chilkat.Hashtable provides a simple key/value collection for storing string and integer values by key. It can add or replace entries, look up values, test whether keys exist, remove entries, count items, enumerate keys, import URL query parameters, serialize values back to a query string, and save or load the table in XML format.

String and integer values

Store values as strings or integers using straightforward add, replace, and lookup methods.

Fast key lookup

Check whether a key exists and retrieve its value without manually scanning a list or parsing text.

Add, replace, and remove

Maintain a mutable collection by adding new entries, replacing existing values, removing individual keys, or clearing the table.

Enumerate keys

Retrieve the set of keys when application logic needs to loop through the stored entries.

Query string helpers

Import URL query parameters into the table and serialize the table back to a query-string representation.

XML persistence

Save the hashtable to XML or reload it from XML when values need to be persisted or transferred in a simple structured format.

Common pattern: Use Hashtable when application code needs a small mutable key/value table, especially for lookup tables, parsed query parameters, or simple string/integer settings. Add values with AddStr or AddInt, retrieve them with LookupStr or LookupInt, and use XML or query-string methods when the table needs to be saved, loaded, or converted.

For an extended overview, see Hashtable Class Overview.

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, Hashtable } 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 hashtable = new Hashtable()
// ... the native object is released when `hashtable` is garbage collected, or now with hashtable.dispose()

new Hashtable()

Creates the underlying native Chilkat object. Hashtable 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.

dispose(): void

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 {
  hashtable.someMethod(...)
} catch (e) {
  console.log((e as Error).message)   // Hashtable.someMethod(...): <reason>
  console.log(hashtable.lastErrorText)   // the full Chilkat log of the failed call
}

// The same call without blocking the JavaScript thread:
try {
  await hashtable.someMethodAsync(...)
} catch (e) {
  console.log((e as Error).message)   // Hashtable.someMethodAsync: <reason>
}

Properties

Count

// read-only
readonly count: number

Introduced in version 9.5.0.97

The number of entries currently stored in the hashtable.

Each key contributes one entry regardless of whether its value is a string or an integer. Adding a new key increases Count; replacing the value of an existing key does not. Removing an entry decreases it, and Clear resets it to 0.

Term	Meaning
`Count`	The number of stored entries.
Capacity	The number of hash buckets, not a maximum entry count.

Hashtable React Native Reference Documentation

Hashtable

Current Version: 11.6.1

Store, look up, remove, enumerate, import, and serialize key/value pairs.

String and integer values

Fast key lookup

Add, replace, and remove

Enumerate keys

Query string helpers

XML persistence

Object Creation

Errors

Properties

Count

DebugLogFilePath

LastErrorHtml

LastErrorText

LastErrorXml

LastMethodSuccess

VerboseLogging

Version

Methods

AddFromXmlSb

AddInt

AddQueryParams

AddStr

Clear

ClearWithNewCapacity

Contains

ContainsIntKey

GetKeys

LookupInt

LookupStr

Remove

ToQueryString

ToXmlSb