如何使用react- native -html-to-pdf在React native Expo中创建PDF？

Question

我正在尝试使用react-native-html-to-pdf库运行'Hello World‘代码并创建PDF，但我无法在世博会上设置它。你能帮我一下吗？我试着使用命令react-native link。

package.json

{
  "main": "node_modules/expo/AppEntry.js",
  "scripts": {
    "start": "expo start",
    "android": "expo start --android",
    "ios": "expo start --ios",
    "web": "expo start --web",
    "eject": "expo eject"
  },
  "dependencies": {
    "expo": "^35.0.0",
    "react": "16.8.3",
    "react-dom": "16.8.3",
    "react-native": "https://github.com/expo/react-native/archive/sdk-35.0.0.tar.gz",
    "react-native-html-to-pdf": "^0.8.0",
    "react-native-pdf-lib": "^0.2.1",
    "react-native-web": "^0.11.7"
  },
  "devDependencies": {
    "babel-preset-expo": "^7.1.0"
  },
  "private": true
}

App.js

import React, { Component } from 'react';

import {
  Text,
  TouchableHighlight,
  View,
  StyleSheet,
} from 'react-native';

import RNHTMLtoPDF from 'react-native-html-to-pdf';

export default class App extends Component {
  async createPDF() {
    let options = {
      html: '<h1>PDF TEST</h1>',
      fileName: 'test',
      directory: 'Documents',
    };

    let file = await RNHTMLtoPDF.convert(options)
    // console.log(file.filePath);
    alert(file.filePath);
  }

  render() {
    return(
      <View style={styles.container}>
        <TouchableHighlight onPress={this.createPDF}>
          <Text>Create PDF</Text>
        </TouchableHighlight>
      </View>
    )
  }
}

const styles = StyleSheet.create({
  container: {
    flex: 1,
    justifyContent: 'center',
    alignItems: 'center',
    backgroundColor: '#F5FCFF',
  },

});```

Answer 1

如果您使用的是expo，则不能链接任何库。这就是世博会的局限性。如果你想拥有这样的功能，最好通过退出expo来切换到纯react原生应用，因为链接在expo中是不起作用的。这是世博会的一个主要限制。

或者你可以查看世博会的文档，

expo link

他们定义了一个打印函数将html保存到pdf。

Print.printToFileAsync(options)
Prints HTML to PDF file and saves it to app's cache directory.
Arguments
options (object) -- A map of options:
html (string) -- HTML string to print into PDF file.
width (number) -- Width of the single page in pixels. Defaults to 612 which is a width of US Letter paper format with 72 PPI.
height (number) -- Height of the single page in pixels. Defaults to 792 which is a height of US Letter paper format with 72 PPI.
base64 (boolean) -- Whether to include base64 encoded string of the file in the returned object.
Returns
Resolves to an object with following keys:
uri (string) -- A URI to the printed PDF file.
numberOfPages (number) -- Number of pages that were needed to render given content.
base64 (string) -- Base64 encoded string containing the data of the PDF file. Available only if base64 option is truthy. It doesn't include data URI prefix data:application/pdf;base64,.

希望能有所帮助。请不要有疑问