exceljs
Version:
Excel Workbook Manager - Read and Write xlsx and csv Files.
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JavaScript
/**
* Copyright (c) 2014-2017 Guyon Roche
* LICENCE: MIT - please refer to LICENCE file included with this module
* or https://github.com/guyonroche/exceljs/blob/master/LICENSE
*/
'use strict';
// =========================================================================
// Column Letter to Number conversion
var colCache = module.exports = {
_dictionary: ['A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z'],
_l2n: {},
_n2l: [],
_level: function _level(n) {
if (n <= 26) {
return 1;
}
if (n <= 26 * 26) {
return 2;
}
return 3;
},
_fill: function _fill(level) {
var c, v, l1, l2, l3;
var n = 1;
if (level >= 1) {
while (n <= 26) {
c = this._dictionary[n - 1];
this._n2l[n] = c;
this._l2n[c] = n;
n++;
}
}
if (level >= 2) {
while (n <= 26 + 26 * 26) {
v = n - (26 + 1);
l1 = v % 26;
l2 = Math.floor(v / 26);
c = this._dictionary[l2] + this._dictionary[l1];
this._n2l[n] = c;
this._l2n[c] = n;
n++;
}
}
if (level >= 3) {
while (n <= 16384) {
v = n - (26 * 26 + 26 + 1);
l1 = v % 26;
l2 = Math.floor(v / 26) % 26;
l3 = Math.floor(v / (26 * 26));
c = this._dictionary[l3] + this._dictionary[l2] + this._dictionary[l1];
this._n2l[n] = c;
this._l2n[c] = n;
n++;
}
}
},
l2n: function l2n(l) {
if (!this._l2n[l]) {
this._fill(l.length);
}
if (!this._l2n[l]) {
throw new Error('Out of bounds. Invalid column letter: ' + l);
}
return this._l2n[l];
},
n2l: function n2l(n) {
if (n < 1 || n > 16384) {
throw new Error('' + n + ' is out of bounds. Excel supports columns from 1 to 16384');
}
if (!this._n2l[n]) {
this._fill(this._level(n));
}
return this._n2l[n];
},
// =========================================================================
// Address processing
_hash: {},
// check if value looks like an address
validateAddress: function validateAddress(value) {
if (!value.match(/^[A-Z]+\d+$/)) {
throw new Error('Invalid Address: ' + value);
}
return true;
},
// convert address string into structure
decodeAddress: function decodeAddress(value) {
var addr = this._hash[value];
if (addr) {
return addr;
}
var col = value.match(/[A-Z]+/)[0];
var colNumber = this.l2n(col);
var row = value.match(/\d+/)[0];
var rowNumber = parseInt(row, 10);
// in case $row$col
value = col + row;
var address = {
address: value,
col: colNumber,
row: rowNumber,
$col$row: '$' + col + '$' + row
};
// mem fix - cache only the tl 100x100 square
if (colNumber <= 100 && rowNumber <= 100) {
this._hash[value] = address;
this._hash[address.$col$row] = address;
}
return address;
},
// convert r,c into structure (if only 1 arg, assume r is address string)
getAddress: function getAddress(r, c) {
if (c) {
var address = this.n2l(c) + r;
return this.decodeAddress(address);
}
return this.decodeAddress(r);
},
// convert [address], [tl:br] into address structures
decode: function decode(value) {
var parts = value.split(':');
if (parts.length === 2) {
var tl = this.decodeAddress(parts[0]);
var br = this.decodeAddress(parts[1]);
var result = {
top: Math.min(tl.row, br.row),
left: Math.min(tl.col, br.col),
bottom: Math.max(tl.row, br.row),
right: Math.max(tl.col, br.col)
};
// reconstruct tl, br and dimensions
result.tl = this.n2l(result.left) + result.top;
result.br = this.n2l(result.right) + result.bottom;
result.dimensions = result.tl + ':' + result.br;
return result;
}
return this.decodeAddress(value);
},
// convert [sheetName!][$]col[$]row[[$]col[$]row] into address or range structures
decodeEx: function decodeEx(value) {
var groups = value.match(/(?:(?:(?:'((?:[^']|'')*)')|([^'^ !]*))!)?(.*)/);
var sheetName = groups[1] || groups[2]; // Qouted and unqouted groups
var reference = groups[3]; // Remaining address
var parts = reference.split(':');
if (parts.length > 1) {
var tl = this.decodeAddress(parts[0]);
var br = this.decodeAddress(parts[1]);
var top = Math.min(tl.row, br.row);
var left = Math.min(tl.col, br.col);
var bottom = Math.max(tl.row, br.row);
var right = Math.max(tl.col, br.col);
tl = this.n2l(left) + top;
br = this.n2l(right) + bottom;
return {
top: top,
left: left,
bottom: bottom,
right: right,
sheetName: sheetName,
tl: { address: tl, col: left, row: top, $col$row: '$' + this.n2l(left) + '$' + top, sheetName: sheetName },
br: { address: br, col: right, row: bottom, $col$row: '$' + this.n2l(right) + '$' + bottom, sheetName: sheetName },
dimensions: tl + ':' + br
};
} else if (reference.startsWith('#')) {
return sheetName ? { sheetName: sheetName, error: reference } : { error: reference };
}
var address = this.decodeAddress(reference);
return sheetName ? Object.assign({ sheetName: sheetName }, address) : address;
},
// convert row,col into address string
encodeAddress: function encodeAddress(row, col) {
return colCache.n2l(col) + row;
},
// convert row,col into string address or t,l,b,r into range
encode: function encode() {
switch (arguments.length) {
case 2:
return colCache.encodeAddress(arguments[0], arguments[1]);
case 4:
return colCache.encodeAddress(arguments[0], arguments[1]) + ':' + colCache.encodeAddress(arguments[2], arguments[3]);
default:
throw new Error('Can only encode with 2 or 4 arguments');
}
}
};
//# sourceMappingURL=col-cache.js.map