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christopherscott/ExcelToJsDate.js

Created May 24, 2012 16:40
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Convert Excel date values to JavaScript date objects
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ExcelToJsDate.js
// Convert Excel dates into JS date objects
//
// @param excelDate {Number}
// @return {Date}
function getJsDateFromExcel(excelDate) {
// JavaScript dates can be constructed by passing milliseconds
// since the Unix epoch (January 1, 1970) example: new Date(12312512312);
// 1. Subtract number of days between Jan 1, 1900 and Jan 1, 1970, plus 1 (Google "excel leap year bug")
// 2. Convert to milliseconds.
return new Date((excelDate - (25567 + 1))*86400*1000);
}
@vijaykk17
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If I Number format the date column as 'Number' and want to receive only number after applying the functionit should not be converted to date. For example

Date

| 44000|

should be visible as 44000 in js also . If I could get the Number format of Excel column somehow in js

@rahul7007
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rahul7007 commented Sep 28, 2020 •
edited

  1. install excel-date-to-js package (npm i excel-date-to-js)
  2. Run this snippet:
    const { getJsDateFromExcel } = require("excel-date-to-js")
    getJsDateFromExcel(dateFieldFromExcelFile)

@devexpert7
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You're a legend! Much appreciated!

By the way, I also had to adjust the value to 2 days such as: new Date((excelDate - (25567 + 2))_86400_1000)

What should be the excel field format? I tried with date format but get error as "The left-hand side of an arithmetic operation must be of type 'any', 'number', 'bigint' or an enum type.ts(2362)".
Also, text format did not help. Number format is not readable to user.

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