75 行
2.9 KiB
JavaScript
75 行
2.9 KiB
JavaScript
// pwuniapp/common/barcode.js
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// 轻量级原生 Code128 条形码编码与图形数据生成器 (零第三方依赖，跨端兼容小程序与H5)
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const CODE128_PATTERNS = [
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'212222', '222122', '222221', '121223', '121322', '131222', '122213', '122312', '132212', '221213', // 0-9
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'221312', '231212', '112232', '122132', '122231', '113222', '123122', '123221', '223211', '221132', // 10-19
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'221231', '213212', '223112', '312131', '311222', '321122', '321221', '312212', '322112', '322211', // 20-29
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'212123', '212321', '232121', '111323', '131123', '131321', '112313', '132113', '132311', '211313', // 30-39
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'231113', '231311', '112133', '112331', '132131', '113123', '113321', '133121', '313121', '211331', // 40-49
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'231131', '213113', '213311', '213131', '311123', '311321', '331121', '312113', '312311', '332111', // 50-59
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'314111', '221411', '431111', '111224', '111422', '121124', '121421', '141122', '141221', '112214', // 60-69
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'112412', '122114', '122411', '142112', '142211', '241211', '221114', '413111', '241112', '134111', // 70-79
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'111242', '121142', '121241', '114212', '124112', '124211', '411212', '421112', '421211', '212141', // 80-89
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'214121', '412121', '111143', '111341', '131141', '114113', '114311', '411113', '411311', '113141', // 90-99
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'114131', '311141', '411131', '211412', '211214', '211232', '2331112' // 100-106
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];
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// Start B 对应 index 104
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const START_B_INDEX = 104;
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// Stop 对应 index 106
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const STOP_INDEX = 106;
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/**
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* 将字符串编码为 Code128B 的条块分布
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* @param {string} text 要编码的文本字符串 (ASCII 32 - 126)
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* @returns {Array<{ isBar: boolean, width: number }>} 条块序列
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*/
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export function encodeCode128B(text) {
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if (!text) text = '0000';
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const codes = [START_B_INDEX];
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let checkSum = START_B_INDEX;
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for (let i = 0; i < text.length; i++) {
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const charCode = text.charCodeAt(i);
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// Code 128B 映射: ASCII 32~127 对应 code 0~95
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let val = charCode - 32;
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if (val < 0 || val > 95) val = 0; // 越界字符转为空格
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codes.push(val);
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checkSum += val * (i + 1);
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}
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const checkVal = checkSum % 103;
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codes.push(checkVal);
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codes.push(STOP_INDEX);
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// 转换为高精度条空阵列 (Bar and Space array)
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const segments = [];
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codes.forEach((codeIndex) => {
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const pattern = CODE128_PATTERNS[codeIndex];
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if (!pattern) return;
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for (let p = 0; p < pattern.length; p++) {
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const width = parseInt(pattern[p], 10);
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const isBar = p % 2 === 0;
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segments.push({ isBar, width });
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}
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});
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return segments;
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}
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/**
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* 转换为 0/1 位图序列 (用于像素级精确渲染)
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* @param {string} text
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* @returns {string} 由 '1' 和 '0' 组成的二进制序列
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*/
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export function getBarcodeBits(text) {
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const segments = encodeCode128B(text);
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let bits = '';
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segments.forEach((seg) => {
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bits += (seg.isBar ? '1' : '0').repeat(seg.width);
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});
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return bits;
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}
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