JsonArray React Native Reference Documentation

JsonArray

Current Version: 11.6.1

Chilkat.JsonArray

Read, modify, search, and emit ordered JSON arrays.

Chilkat.JsonArray is the JSON array companion to Chilkat.JsonObject. It represents an ordered list of JSON values and provides index-based methods for reading, inserting, replacing, deleting, swapping, searching, and emitting array data. It supports scalar values, nested objects, nested arrays, date/time parsing, exact numeric string handling, compact or pretty output, and search helpers for arrays of strings or arrays of objects.

Ordered JSON values

Work with JSON arrays as ordered lists containing strings, numbers, booleans, nulls, objects, arrays, and mixed value types.

Index-based access

Retrieve, insert, replace, delete, or swap values by array index when processing JSON list data.

Nested objects and arrays

Access child JsonObject and JsonArray values to navigate and modify deeper JSON structures.

Search helpers

Search arrays of strings or arrays of objects to locate matching values without manually scanning every element.

Date and numeric handling

Parse date/time values and preserve exact numeric strings when JSON data contains values that must not be rounded or reformatted.

Emit JSON output

Produce compact or pretty JSON output after array data has been loaded, edited, searched, or built programmatically.

Common pattern: Use JsonObject to navigate named members and JSON paths, then use JsonArray to iterate or modify ordered lists found within the object tree. Retrieve nested objects or arrays as needed, update values by index, and emit the final JSON in compact or pretty form.

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

Creates the underlying native Chilkat object. JsonArray 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 {
  jsonArray.someMethod(...)
} catch (e) {
  console.log((e as Error).message)   // JsonArray.someMethod(...): <reason>
  console.log(jsonArray.lastErrorText)   // the full Chilkat log of the failed call
}

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

Properties

DebugLogFilePath
// read/write
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.

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EmitCompact
// read/write
emitCompact: boolean
Introduced in version 9.5.0.64

Controls whether emitted JSON is compact or pretty-formatted. If true, output contains no unnecessary whitespace and is emitted on a single line. If false, indentation and line breaks are added for readability. The default is true.

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EmitCrlf
// read/write
emitCrlf: boolean
Introduced in version 9.5.0.64

Controls line endings when pretty-formatted JSON is emitted. If true, line breaks use CRLF ( ); if false, they use LF ( ). The default is true.

Applies only to pretty output: When EmitCompact is true, the JSON is emitted on one line and this setting has no effect.

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FindStartIndex
// read/write
findStartIndex: number
Introduced in version 11.6.0

Specifies the zero-based array index at which FindString and FindObject begin searching. The default value is 0.

Iterating matches: After finding a match at index n, set this property to n + 1 before the next search to continue with later elements.

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LastErrorHtml
// read-only
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.

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LastErrorText
// read-only
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.

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LastErrorXml
// read-only
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.

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LastMethodSuccess
// read/write
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.

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Size
// read-only
readonly size: number
Introduced in version 9.5.0.56

Returns the number of values currently contained in the JSON array. Array indexes therefore range from 0 through Size - 1.

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VerboseLogging
// read/write
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.

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Version
// read-only
readonly version: string

Version of the component/library, such as "10.1.0"

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Methods

AddArrayAt
addArrayAt(index: number): void
Introduced in version 9.5.0.56

Inserts a new, empty JSON array at zero-based position index. Existing elements at that position and after it are shifted one position toward the end of the array.

0Insert as the first array element.
-1Append as the last array element.
nInsert at zero-based position n.
Insert vs. replace: The Add*At methods insert a new array element. Use the corresponding Set*At method when replacing an existing element.

Returns normally on success; throws an Error on failure.

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AddArrayAt2
addArrayAt2(index: number, jarr: JsonArray): void
Introduced in version 11.1.0

Inserts a new, empty JSON array at zero-based position index and updates jarr to reference the newly inserted array.

0Insert as the first array element.
-1Append as the last array element.
nInsert at zero-based position n.
Immediate editing: Because jarr references the inserted array, it can be populated directly without a separate ArrayAt lookup.

Returns normally on success; throws an Error on failure.

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AddBoolAt
addBoolAt(index: number, value: boolean): void
Introduced in version 9.5.0.56

Inserts a new JSON boolean value at zero-based position index. Existing elements at that position and after it are shifted one position toward the end of the array.

0Insert as the first array element.
-1Append as the last array element.
nInsert at zero-based position n.
Insert vs. replace: The Add*At methods insert a new array element. Use the corresponding Set*At method when replacing an existing element.

Returns normally on success; throws an Error on failure.

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AddIntAt
addIntAt(index: number, value: number): void
Introduced in version 9.5.0.56

Inserts a new JSON integer value at zero-based position index. Existing elements at that position and after it are shifted one position toward the end of the array.

0Insert as the first array element.
-1Append as the last array element.
nInsert at zero-based position n.
Insert vs. replace: The Add*At methods insert a new array element. Use the corresponding Set*At method when replacing an existing element.

Returns normally on success; throws an Error on failure.

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AddNullAt
addNullAt(index: number): void
Introduced in version 9.5.0.56

Inserts a JSON null value at zero-based position index. Existing elements at that position and after it are shifted one position toward the end of the array.

0Insert as the first array element.
-1Append as the last array element.
nInsert at zero-based position n.
Insert vs. replace: The Add*At methods insert a new array element. Use the corresponding Set*At method when replacing an existing element.

Returns normally on success; throws an Error on failure.

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AddNumberAt
addNumberAt(index: number, numericStr: string): void
Introduced in version 9.5.0.56

Inserts a JSON number at zero-based position index. The numericStr argument supplies the exact JSON numeric text to store. Existing elements at that position and after it are shifted one position toward the end of the array.

0Insert as the first array element.
-1Append as the last array element.
nInsert at zero-based position n.
Exact numeric text: Use this method when lexical form or precision matters, for example 12345678901234567890, 1.2500, or scientific notation. The supplied text must be valid JSON number syntax; JSON does not permit NaN or infinity.

Returns normally on success; throws an Error on failure.

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AddObjectAt
addObjectAt(index: number): void
Introduced in version 9.5.0.56

Inserts a new, empty JSON object at zero-based position index. Existing elements at that position and after it are shifted one position toward the end of the array.

0Insert as the first array element.
-1Append as the last array element.
nInsert at zero-based position n.
Insert vs. replace: The Add*At methods insert a new array element. Use the corresponding Set*At method when replacing an existing element.

Returns normally on success; throws an Error on failure.

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AddObjectAt2
addObjectAt2(index: number, json: JsonObject): void
Introduced in version 11.1.0

Inserts a new, empty JSON object at zero-based position index and updates json to reference the newly inserted object.

0Insert as the first array element.
-1Append as the last array element.
nInsert at zero-based position n.
Immediate editing: Because json references the inserted object, it can be populated directly without a separate ObjectAt lookup.

Returns normally on success; throws an Error on failure.

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AddObjectCopyAt
addObjectCopyAt(index: number, jsonObj: JsonObject): void
Introduced in version 9.5.0.82

Inserts an independent copy of jsonObj at zero-based position index. Existing elements at that position and after it are shifted one position toward the end of the array.

0Insert as the first array element.
-1Append as the last array element.
nInsert at zero-based position n.
Copy semantics: The inserted object is copied rather than referenced. Later changes to the source jsonObj do not serve as edits to the inserted array value.

Returns normally on success; throws an Error on failure.

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AddStringAt
addStringAt(index: number, value: string): void
Introduced in version 9.5.0.56

Inserts a new JSON string value at zero-based position index. Existing elements at that position and after it are shifted one position toward the end of the array.

0Insert as the first array element.
-1Append as the last array element.
nInsert at zero-based position n.
Insert vs. replace: The Add*At methods insert a new array element. Use the corresponding Set*At method when replacing an existing element.

Returns normally on success; throws an Error on failure.

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AddUIntAt
addUIntAt(index: number, value: number): void
Introduced in version 9.5.0.96

Inserts a new JSON unsigned integer value at zero-based position index. Existing elements at that position and after it are shifted one position toward the end of the array.

0Insert as the first array element.
-1Append as the last array element.
nInsert at zero-based position n.
Insert vs. replace: The Add*At methods insert a new array element. Use the corresponding Set*At method when replacing an existing element.

Returns normally on success; throws an Error on failure.

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AppendArrayItems
appendArrayItems(jarr: JsonArray): void
Introduced in version 9.5.0.82

Appends copies of all values from jarr to the end of this array, preserving their order.

Source is unchanged: The source array is not emptied or moved. This method is useful for concatenating JSON arrays, including arrays belonging to different JSON documents.

Returns normally on success; throws an Error on failure.

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ArrayAt
arrayAt(index: number): JsonArray
Introduced in version 9.5.0.56

Returns the nested JSON array stored at zero-based position index.

Reference, not copy: The returned JsonArray refers to the existing nested array in the same JSON document. Changes made through the returned object modify that nested array.
Type requirement: The value at index must be an array. Use TypeAt when the value type is not already known.

Throws an Error on failure (where the description says null is returned, the method throws instead).

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ArrayAt2
arrayAt2(index: number, jarr: JsonArray): void
Introduced in version 11.0.0

Updates jarr so that it references the nested JSON array stored at zero-based position index.

Reference, not copy: Changes made through jarr modify the existing nested array in the same JSON document.

Returns normally on success; throws an Error on failure.

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BoolAt
boolAt(index: number): boolean
Introduced in version 9.5.0.56

Returns the boolean value stored at zero-based position index.

Type-aware access: Use TypeAt when the JSON type at index is not already known.
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Clear
clear(): void
Introduced in version 9.5.0.76

Removes all values from the array, leaving an empty JSON array ([]).

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DateAt
dateAt(index: number, dt: CkDateTime): void
Introduced in version 9.5.0.73

Parses the date/time value at zero-based position index and loads the result into dt. Recognized forms include ISO 8601 timestamps (for example, 2009-11-04T19:55:41Z), RFC 822-style date/time strings, and Unix timestamp integers.

JSON has no native date type: Dates are application conventions represented as strings or numbers. These methods recognize common representations and convert them to Chilkat date/time objects.

Returns normally on success; throws an Error on failure.

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DeleteAt
deleteAt(index: number): void
Introduced in version 9.5.0.56

Deletes the value at zero-based position index. Elements following the deleted value shift down by one position.

Returns normally on success; throws an Error on failure.

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DtAt
dtAt(index: number, bLocal: boolean, dt: DtObj): void
Introduced in version 9.5.0.73

Parses the date/time value at zero-based position index and loads the result into dt. If bLocal is true, the populated fields represent local time; if false, they represent UTC/GMT. Recognized forms include ISO 8601 timestamps, RFC 822-style date/time strings, and Unix timestamp integers.

JSON has no native date type: Dates are application conventions represented as strings or numbers. These methods recognize common representations and convert them to Chilkat date/time objects.

Returns normally on success; throws an Error on failure.

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Emit
emit(): string
Introduced in version 9.5.0.58

Serializes this JSON array and returns the resulting JSON text.

Formatting: Set EmitCompact to choose compact versus pretty output. When pretty output is enabled, EmitCrlf selects CRLF or LF line endings.

Throws an Error on failure (where the description says null is returned, the method throws instead).

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EmitSb
emitSb(sb: StringBuilder): void
Introduced in version 9.5.0.65

Serializes this JSON array into the supplied StringBuilder.

Formatting: Set EmitCompact to choose compact versus pretty output. When pretty output is enabled, EmitCrlf selects CRLF or LF line endings.
Large JSON: Using a StringBuilder can avoid returning a very large JSON document as a language-native string before passing it to another Chilkat method or writing it to a file.

Returns normally on success; throws an Error on failure.

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FindObject
findObject(name: string, value: string, caseSensitive: boolean): number
Introduced in version 9.5.0.73

Searches array elements that are JSON objects and returns the zero-based index of the first object whose direct member name has a value matching value. Returns -1 if no match is found. The value pattern may contain *, which matches zero or more characters. Set caseSensitive to control whether letter case must match.

Member name, not JSON path: name identifies a direct member of each object being tested; it is not a JSON path.
Search start: Searching begins at FindStartIndex, whose default is 0. To continue searching after a match, set FindStartIndex to the previous returned index plus 1.
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FindString
findString(value: string, caseSensitive: boolean): number
Introduced in version 9.5.0.73

Searches for the first string array element matching value and returns its zero-based index, or -1 if no match is found. The pattern may contain *, which matches zero or more characters. Set caseSensitive to control whether letter case must match.

Search start: Searching begins at FindStartIndex, whose default is 0. To continue searching after a match, set FindStartIndex to the previous returned index plus 1.
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IntAt
intAt(index: number): number
Introduced in version 9.5.0.56

Returns the integer value stored at zero-based position index.

Type-aware access: Use TypeAt when the JSON type at index is not already known.
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IsNullAt
isNullAt(index: number): boolean
Introduced in version 9.5.0.56

Returns true if the value at zero-based position index is the JSON value null; otherwise returns false.

JSON null: null is a distinct JSON value. It is not the same as an empty string, zero, false, an empty object, or an empty array.
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Load
load(jsonArray: string): void
Introduced in version 9.5.0.64

Parses the JSON array text in jsonArray and loads it into this object. The input must represent a JSON array, beginning with [ and ending with ].

Important — loading detaches the array: Calling this method makes the JsonArray its own independent JSON document. If the object previously referenced an array nested inside another JSON document, that relationship is discarded. For this reason, call Load/LoadSb on a new JsonArray instance.

Returns normally on success; throws an Error on failure.

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LoadSb
loadSb(sb: StringBuilder): void
Introduced in version 9.5.0.64

Parses the JSON array contained in sb and loads it into this object. The input must represent a JSON array, beginning with [ and ending with ].

Important — loading detaches the array: Calling this method makes the JsonArray its own independent JSON document. If the object previously referenced an array nested inside another JSON document, that relationship is discarded. For this reason, call Load/LoadSb on a new JsonArray instance.

Returns normally on success; throws an Error on failure.

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ObjectAt
objectAt(index: number): JsonObject
Introduced in version 9.5.0.56

Returns the JSON object stored at zero-based position index.

Reference, not copy: The returned JsonObject refers to the existing object in the same JSON document. Changes made through the returned object modify that nested object.
Type requirement: The value at index must be an object. Use TypeAt when the value type is not already known.

Throws an Error on failure (where the description says null is returned, the method throws instead).

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ObjectAt2
objectAt2(index: number, jsonObj: JsonObject): void
Introduced in version 11.0.0

Updates jsonObj so that it references the JSON object stored at zero-based position index.

Reference, not copy: Changes made through jsonObj modify the existing object in the same JSON document.

Returns normally on success; throws an Error on failure.

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SetBoolAt
setBoolAt(index: number, value: boolean): void
Introduced in version 9.5.0.56

Replaces the value at zero-based position index with the specified JSON boolean value. The array length and the positions of other elements are unchanged.

Returns normally on success; throws an Error on failure.

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SetIntAt
setIntAt(index: number, value: number): void
Introduced in version 9.5.0.56

Replaces the value at zero-based position index with the specified JSON integer value. The array length and the positions of other elements are unchanged.

Returns normally on success; throws an Error on failure.

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SetNullAt
setNullAt(index: number): void
Introduced in version 9.5.0.56

Replaces the value at zero-based position index with the JSON value null. The array length and the positions of other elements are unchanged.

Returns normally on success; throws an Error on failure.

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SetNumberAt
setNumberAt(index: number, value: string): void
Introduced in version 9.5.0.56

Replaces the value at zero-based position index with a JSON number. The value argument supplies the exact JSON numeric text to store.

Exact numeric text: Use this method when lexical form or precision matters. The supplied text must be valid JSON number syntax; JSON does not permit NaN or infinity.

Returns normally on success; throws an Error on failure.

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SetStringAt
setStringAt(index: number, value: string): void
Introduced in version 9.5.0.56

Replaces the value at zero-based position index with the specified JSON string value. The array length and the positions of other elements are unchanged.

Returns normally on success; throws an Error on failure.

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SetUIntAt
setUIntAt(index: number, value: number): void
Introduced in version 9.5.0.96

Replaces the value at zero-based position index with the specified JSON unsigned integer value. The array length and the positions of other elements are unchanged.

Returns normally on success; throws an Error on failure.

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StringAt
stringAt(index: number): string
Introduced in version 9.5.0.56

Returns the string value stored at zero-based position index.

Type-aware access: Use TypeAt when the JSON type at index is not already known.

Throws an Error on failure (where the description says null is returned, the method throws instead).

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Swap
swap(index1: number, index2: number): void
Introduced in version 9.5.0.76

Exchanges the values at zero-based positions index1 and index2. The array length does not change.

Returns normally on success; throws an Error on failure.

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TypeAt
typeAt(index: number): number
Introduced in version 9.5.0.58

Returns an integer identifying the JSON type of the value at zero-based position index. Returns -1 if no value exists at that index.

1string
2number
3object
4array
5boolean
6null
Why use TypeAt: JSON arrays may contain mixed types. Checking the type first avoids choosing a type-specific accessor such as ObjectAt, ArrayAt, or IntAt for the wrong kind of value.
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UIntAt
uIntAt(index: number): number
Introduced in version 9.5.0.96

Returns the unsigned integer value stored at zero-based position index.

Type-aware access: Use TypeAt when the JSON type at index is not already known.
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