jutools

A collection of utility functions for JavaScript development.

Installation

npm install jutools

Usage

import { objEqual, getCookie, setCookie, deleteCookie, calculateCarousel, getDiffArr, mergeSameObj, cumNumberFromArrSameItem, translateArray, queueArr, getQueryParam, visitDevice, debounce, throttle, exportFile, downloadFile, preLoadImg, checkFileType, getBase64, amountFormat, deepCopy, randomString, randomNumber } from "jutools";

API

objEqual(a, b)

Compares two objects for equality.

Parameters:

• a (Object): First object.
• b (Object): Second object.

Returns:

• boolean: Whether the objects are equal.

getCookie(key)

Retrieves a cookie value by key.

Parameters:

• key (string): The cookie key.

Returns:

• string | null: The cookie value, or null if not found.

setCookie(key, value, expiration)

Sets a cookie.

Parameters:

• key (string): The cookie key.
• value (string): The cookie value.
• expiration (number): Expiration time in milliseconds.

deleteCookie(key)

Deletes a cookie by setting its expiration to the past.

Parameters:

• key (string): The cookie key.

calculateCarousel(allData, eachPageNum)

Splits a one-dimensional array into a two-dimensional array based on a given page size.

Parameters:

• allData (Array): The original array.
• eachPageNum (number): Number of items per page.

Returns:

• Array<Array<any>>: The two-dimensional array.

getDiffArr(arr1, arr2)

Finds the elements that exist in arr1 but not in arr2.

Parameters:

• arr1 (Array): First array.
• arr2 (Array): Second array.

Returns:

• Array<any>: Array of differing elements.

mergeSameObj(arr, key)

Merges objects with the same key into sub-arrays.

Parameters:

• arr (Array): Array of objects.
• key (string): Key to group by.

Returns:

• Array<Array<Object>>: Grouped objects as a two-dimensional array.

cumNumberFromArrSameItem(data_arr, judg_key, number_key)

Merges objects with the same judg_key and sums up the number_key field.

Parameters:

• data_arr (Array): Array of objects.
• judg_key (string): Key to merge objects by.
• number_key (string): Key whose values should be summed.

Returns:

• Array<Object>: Array with merged objects.

translateArray(array, targetkey)

Converts a one-dimensional array into a two-dimensional array grouped by targetkey.

Parameters:

• array (Array): Original array.
• targetkey (string): Key to group by.

Returns:

• Array<Array<Object>>: Grouped array.

queueArr(arr, size)

Generates unique permutations of an array.

Parameters:

• arr (Array): The input array.
• size (number): The number of elements in each permutation.

Returns:

• Array<Array<any>>: An array of unique permutations.

getQueryParam(param)

Retrieves a query parameter value from the URL.

Parameters:

• param (string): The query parameter key.

Returns:

• string | null: The parameter value or null if not found.

visitDevice()

Detects the user's device type.

Returns:

• string: Device type (e.g., 'mobile', 'desktop').

debounce(fn, delay)

Creates a debounced function that delays execution.

Parameters:

• fn (Function): Function to debounce.
• delay (number): Delay in milliseconds.

throttle(fn, delay)

Creates a throttled function that limits execution frequency.

Parameters:

• fn (Function): Function to throttle.
• delay (number): Delay in milliseconds.

exportFile(data, filename, type)

Exports data as a file.

Parameters:

• data (string | Blob): File content.
• filename (string): File name.
• type (string): MIME type.

downloadFile(url, filename)

Downloads a file from a given URL.

Parameters:

• url (string): File URL.
• filename (string): File name.

preLoadImg(urls)

Preloads images.

Parameters:

• urls (Array): List of image URLs.

checkFileType(file, allowedTypes)

Checks if a file type is allowed.

Parameters:

• file (File): The file object.
• allowedTypes (Array): Allowed MIME types.

Returns:

• boolean: Whether the file type is allowed.

getBase64(file)

Converts a file to a base64 string.

Parameters:

• file (File): The file object.

Returns:

• Promise<string>: A promise that resolves to the base64 string.

amountFormat(number, decimals)

Formats a number with commas.

Parameters:

• number (number): The input number.
• decimals (number): Number of decimal places.

Returns:

• string: Formatted number string.

deepCopy(obj)

Performs a deep copy of an object.

Parameters:

• obj (Object): The object to copy.

Returns:

• Object: The deep-copied object.

randomString(length)

Generates a random string.

Parameters:

• length (number): Desired string length.

Returns:

• string: Random string.

randomNumber(min, max)

Generates a random number in a given range.

Parameters:

• min (number): Minimum value.
• max (number): Maximum value.

Returns:

• number: Random number in the range.