HarmonyOS 鸿蒙Next实现颜色值HEX与RGBA互相转换

HarmonyOS 鸿蒙Next实现颜色值HEX与RGBA互相转换

/**
 * 将 #AARRGGBB 十六进制转换为 (R, G, B, alpha%)
 * @param hex 十六进制颜色值，格式为 #AARRGGBB 或 #RRGGBB
 * @returns 包含R、G、B和透明度的数组，透明度为百分比值(0-100)
 */
static hexToRGBA(hex: string): string[] {
  try {
    // 1. 去除 # 号并统一大写
    const cleanHex = hex.replace(/^#/, '').toUpperCase();

    // 校验格式 (支持 8 位 ARGB 或 6 位 RGB)
    if (!/^(?:[0-9A-F]{8}|[0-9A-F]{6})$/.test(cleanHex)) {
      throw new Error("Invalid hex color format");
    }

    // 2. 补充 Alpha 通道 (如果是 6 位 RGB，默认 Alpha 为 FF)
    const fullHex = cleanHex.length === 6 ? `FF${cleanHex}` : cleanHex;

    // 3. 解析十六进制值
    const alphaHex = fullHex.substring(0, 2);
    const redHex = fullHex.substring(2, 4);
    const greenHex = fullHex.substring(4, 6);
    const blueHex = fullHex.substring(6, 8);

    // 4. 转换为十进制数值
    const alpha = Math.round((parseInt(alphaHex, 16) / 255) * 100); // Alpha 转百分比
    const red = parseInt(redHex, 16);
    const green = parseInt(greenHex, 16);
    const blue = parseInt(blueHex, 16);

    return [red.toString(), green.toString(), blue.toString(), alpha.toString()];
  } catch (error) {
    console.error("Hex to RGBA conversion error:", error);
    // 返回默认值
    return ['0', '0', '0', '100'];
  }
}

/**
 * 将 (R, G, B, alpha%) 转换为 #AARRGGBB 十六进制
 * @param red 红色值 0-255
 * @param green 绿色值 0-255
 * @param blue 蓝色值 0-255
 * @param alpha 透明度百分比 0-100
 * @returns 十六进制颜色值，格式为 #AARRGGBB
 */
static rgbaToHex(rgbColor: RGBColor, alpha: string): string {
  try {
    // 1. 将字符串转换为数字
    const redNum = parseInt(rgbColor.red);
    const greenNum = parseInt(rgbColor.green);
    const blueNum = parseInt(rgbColor.blue);
    const alphaNum = parseInt(alpha);
    
    // 2. 校验数值范围
    if (isNaN(redNum) || isNaN(greenNum) || isNaN(blueNum) || isNaN(alphaNum)) {
      throw new Error("Invalid RGBA values: values must be numbers");
    }
    
    if (redNum < 0 || redNum > 255 || greenNum < 0 || greenNum > 255 || blueNum < 0 || blueNum > 255) {
      throw new Error("Invalid RGB values: values must be between 0 and 255");
    }
    
    if (alphaNum < 0 || alphaNum > 100) {
      throw new Error("Invalid alpha value: must be between 0 and 100");
    }

    // 3. 将 Alpha 百分比转换为 0 - 255 的值
    const alphaValue = Math.round((alphaNum / 100) * 255);

    // 4. 转换为十六进制字符串
    const alphaHex = alphaValue.toString(16).padStart(2, '0');
    const redHex = redNum.toString(16).padStart(2, '0');
    const greenHex = greenNum.toString(16).padStart(2, '0');
    const blueHex = blueNum.toString(16).padStart(2, '0');

    // 5. 拼接成完整的十六进制颜色值
    return `#${alphaHex}${redHex}${greenHex}${blueHex}`;
  } catch (error) {
    console.error("RGBA to Hex conversion error:", error);
    // 返回默认值
    return '#FF000000';
  }
}