text: import {PixelRatio, Dimensions} from 'react-native';
  
  const pixelRatio = PixelRatio.get();
  const deviceHeight = Dimensions.get('window').height;
  const deviceWidth = Dimensions.get('window').width;
  
  export const normalize = size => {
    if (pixelRatio >= 2 && pixelRatio < 3) {
      // iphone 5s and older Androids
      if (deviceWidth < 360) {
        return size * 0.95;
      }
      // iphone 5
      if (deviceHeight < 667) {
        return size;
        // iphone 6-6s
      }
      if (deviceHeight >= 667 && deviceHeight <= 735) {
        return size * 1.15;
      }
      // older phablets
      return size * 1.25;
    }
    if (pixelRatio >= 3 && pixelRatio < 3.5) {
      // catch Android font scaling on small machines
      // where pixel ratio / font scale ratio => 3:3
      if (deviceWidth <= 360) {
        return size;
      }
      // Catch other weird android width sizings
      if (deviceHeight < 667) {
        return size * 1.15;
        // catch in-between size Androids and scale font up
        // a tad but not too much
      }
      if (deviceHeight >= 667 && deviceHeight <= 735) {
        return size * 1.2;
      }
      // catch larger devices
      // ie iphone 6s plus / 7 plus / mi note 等等
      return size * 1.27;
    }
    if (pixelRatio >= 3.5) {
      // catch Android font scaling on small machines
      // where pixel ratio / font scale ratio => 3:3
      if (deviceWidth <= 360) {
        return size;
        // Catch other smaller android height sizings
      }
      if (deviceHeight < 667) {
        return size * 1.2;
        // catch in-between size Androids and scale font up
        // a tad but not too much
      }
      if (deviceHeight >= 667 && deviceHeight <= 735) {
        return size * 1.25;
      }
      // catch larger phablet devices
      return size * 1.4;
    }
    // if older device ie pixelRatio !== 2 || 3 || 3.5
    return size;
  };
  
  export function isASCII(str) {
    return /^[\x00-\x7F]*$/.test(str);
  }
  