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exceljs

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Excel Workbook Manager - Read and Write xlsx and csv Files.

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"use strict"; // StringBuf - a way to keep string memory operations to a minimum // while building the strings for the xml files class StringBuf { constructor(options) { this._buf = Buffer.alloc(options && options.size || 16384); this._encoding = options && options.encoding || 'utf8'; // where in the buffer we are at this._inPos = 0; // for use by toBuffer() this._buffer = undefined; } get length() { return this._inPos; } get capacity() { return this._buf.length; } get buffer() { return this._buf; } toBuffer() { // return the current data as a single enclosing buffer if (!this._buffer) { this._buffer = Buffer.alloc(this.length); this._buf.copy(this._buffer, 0, 0, this.length); } return this._buffer; } reset(position) { position = position || 0; this._buffer = undefined; this._inPos = position; } _grow(min) { let size = this._buf.length * 2; while (size < min) { size *= 2; } const buf = Buffer.alloc(size); this._buf.copy(buf, 0); this._buf = buf; } addText(text) { this._buffer = undefined; let inPos = this._inPos + this._buf.write(text, this._inPos, this._encoding); // if we've hit (or nearing capacity), grow the buf while (inPos >= this._buf.length - 4) { this._grow(this._inPos + text.length); // keep trying to write until we've completely written the text inPos = this._inPos + this._buf.write(text, this._inPos, this._encoding); } this._inPos = inPos; } addStringBuf(inBuf) { if (inBuf.length) { this._buffer = undefined; if (this.length + inBuf.length > this.capacity) { this._grow(this.length + inBuf.length); } // eslint-disable-next-line no-underscore-dangle inBuf._buf.copy(this._buf, this._inPos, 0, inBuf.length); this._inPos += inBuf.length; } } } module.exports = StringBuf; //# sourceMappingURL=string-buf.js.map