um-react/src/SelectFile.tsx

import React, { useId } from 'react';

import { Box, Text } from '@chakra-ui/react';
import { UnlockIcon } from '@chakra-ui/icons';
import { useAppDispatch } from './hooks';
import { addNewFile, processFile } from './features/file-listing/fileListingSlice';
import { nanoid } from 'nanoid';

export function SelectFile() {
  const dispatch = useAppDispatch();
  const id = useId();

  const handleFileSelection = (e: React.ChangeEvent<HTMLInputElement>) => {
    if (e.target.files) {
      for (const file of e.target.files) {
        const blobURI = URL.createObjectURL(file);
        const fileName = file.name;
        const fileId = 'file://' + nanoid();
        // FIXME: this should be a single action/thunk that first adds the item, then updates it.
        dispatch(
          addNewFile({
            id: fileId,
            blobURI,
            fileName,
          })
        );
        dispatch(processFile({ fileId }));
      }
    }

    e.target.value = '';
  };

  return (
    <Box
      as="label"
      htmlFor={id}
      w="100%"
      maxW={480}
      borderWidth="1px"
      borderRadius="lg"
      transitionDuration="0.5s"
      p="6"
      cursor="pointer"
      display="flex"
      flexDir="column"
      alignItems="center"
      _hover={{
        borderColor: 'gray.400',
        bg: 'gray.50',
      }}
    >
      <Box pb={3}>
        <UnlockIcon boxSize={8} />
      </Box>
      <Box textAlign="center">
        {/* 将文件拖到此处，或 */}
        <Text as="span" color="teal.400">
          点我选择
        </Text>
        需要解密的文件
        <input id={id} type="file" hidden multiple onChange={handleFileSelection} />
        <Text fontSize="sm" opacity="50%">
          仅在浏览器内对文件进行解锁，无需消耗流量
        </Text>
      </Box>
    </Box>
  );
}