exceljs
Version:
Excel Workbook Manager - Read and Write xlsx and csv Files.
220 lines (200 loc) • 6.88 kB
JavaScript
/**
* Copyright (c) 2014 Guyon Roche
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*
*/
'use strict';
var _ = require('lodash');
// =========================================================================
// 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(n) {
if (n <= 26) { return 1; }
if (n <= 26*26) { return 2; }
return 3;
},
_fill: function(level) {
var c, v, l1, l2, l3;
var n = 1;
if (level >= 1) {
//console.log('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(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(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(value) {
if (!value.match(/^[A-Z]+\d+$/)) {
throw new Error('Invalid Address: ' + value);
}
return true;
},
// convert address string into structure
decodeAddress: function(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);
// 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(r,c) {
if (c) {
var address = this.n2l(c) + r;
return this.decodeAddress(address);
} else {
return this.decodeAddress(r);
}
},
// convert [address], [tl:br] into address structures
decode: function(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;
} else {
return this.decodeAddress(value);
}
},
// convert [sheetName!][$]col[$]row[[$]col[$]row] into address or range structures
decodeEx: function(value) {
var sheetName;
var parts = value.split('!');
if (parts.length > 1) {
value = parts.pop();
sheetName = parts.join('!').replace(/^'|'$/g, '');
}
parts = value.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 {
var address = this.decodeAddress(value);
return sheetName ? _.extend({sheetName: sheetName}, address) : address;
}
},
// convert row,col into address string
encodeAddress: function(row, col) {
return colCache.n2l(col) + row;
},
// convert row,col into string address or t,l,b,r into range
encode: function() {
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');
}
}
};