Editing 索引转 Excel 列字母

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  <title>索引转 Excel 列字母</title>
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function excelColumnIndexAsLetter(n) {
    var cs = 'A'.charCodeAt(0);
    var len = 26;
    var s = "";
    while (n >= 0) {
        s = String.fromCharCode(n % len + cs) + s;
        n = Math.floor(n / len) - 1;
    }
    return s;
}

[0, 26, 52, 999, 9999].forEach(n => {
    console.log(n, excelColumnIndexAsLetter(n))
})