如何在 ReactJs 中使用 dropzone 将文件及其描述添加到状态?

How to add a file and its description to the state using dropzone in ReactJs?

如何使用 select、使用 react-dropzone 将一个或多个文件及其描述添加到组件状态。

我正在使用 Reactjs、dropzone 和 bootstrap,我想要实现的是:添加一个或多个文件(通过将它们拖到一个区域),然后查看已添加文件的列表和 select 每个输入(带有供用户定义“类型”的选项)将所有这些保存在一个状态中,然后将该信息发送到 API。 类似于图像中显示的内容:

我目前的代码,returns 我接受的文件列表,取决于它们的扩展名(pdf、xlsx ...)和拒绝的文件,但我不知道如何添加 select(带有“类型”来自文件的选项,可以是“摘要”、“报告”、“测试”...)并将其保存在状态中,然后将其发送到 API.

我目前使用 react-dropzone 的代码是这样的:

const baseStyle = {
  flex: 1,
  display: "flex",
  flexDirection: "column",
  alignItems: "center",
  padding: "20px",
  borderWidth: 2,
  borderRadius: 20,
  borderColor: "#26C2E7",
  borderStyle: "dashed",
  backgroundColor: "#fafafa",
  color: "#c4c4c4",
  outline: "none",
  transition: "border .24s ease-in-out"
};

const activeStyle = {
  borderColor: "#f2f"
};

const acceptStyle = {
  borderColor: "#f8f"
};

const rejectStyle = {
  borderColor: "#f2f"
};
function InputFiles(props) {
  const {
    acceptedFiles,
    fileRejections,
    isDragActive,
    isDragAccept,
    isDragReject,
    getRootProps,
    getInputProps
  } = reactDropzone.useDropzone({
    accept: ".xlsx,.docx,.pdf"
  });

  const style = React.useMemo(
    () => ({
      ...baseStyle,
      ...(isDragActive ? activeStyle : {}),
      ...(isDragAccept ? acceptStyle : {}),
      ...(isDragReject ? rejectStyle : {})
    }),
    [isDragActive, isDragReject, isDragAccept]
  );

  const acceptedFileItems = acceptedFiles.map((file) => (
    <li key={file.path}>
      {file.path} - {file.size} bytes
    </li>
  ));

  const fileRejectionItems = fileRejections.map(({ file, errors }) => (
    <li key={file.path}>
      {file.path} - {file.size} bytes
      <ul>
        {errors.map((e) => (
          <li key={e.code}>{e.message}</li>
        ))}
      </ul>
    </li>
  ));

  return (
    <section className="container">
      {/* <div {...getRootProps({ style })}> */}
      <div {...getRootProps({ style })}>
        <input {...getInputProps()} />
        <p>Drag 'n' drop some files here, or click to select files</p>
        <em>(Only *.pdf , *.xlsx , *.docx files will be accepted)</em>
      </div>
      <aside>
        <h4>Accepted files</h4>
        <ul>{acceptedFileItems}</ul>
        <h4>Rejected files</h4>
        <ul>{fileRejectionItems}</ul>
      </aside>
    </section>
  );
}

ReactDOM.render(<InputFiles />, document.body);

window.onload = function() {
 console.log('onload');
   
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/16.6.1/umd/react.production.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/prop-types/15.7.2/prop-types.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react-dom/16.6.1/umd/react-dom.production.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react-dropzone/11.2.0/index.js"></script>

目标是得到这样的东西:

添加文件及其描述时,它们必须保存在组件的状态中,objective 单击保存时,会向 [=36= 发出 POST 请求],点击取消时,必须删除状态信息

useDropZone 使用回调 onDrop 可以让您像这样获取文件的名称:

 const onDrop = React.useCallback((acceptedFiles) => {
    // Do something with the files
  }, []);
  const { ... } = useDropzone({ onDrop });

每次删除文件时,一旦有了文件名,就可以将其存储在一个状态中,显示名称和 selects,并在每次 select 出现时相应地更新该状态点击了。

另请注意,doc 表示它应该至少是 React 16.8,但您似乎使用的是 React 16.6。

正如@Emmanuel 在他的回答中提到的那样,您可以将文件存储在一个状态中,此实现使用名称作为键将文件存储在映射中。

import React, { useMemo, useState } from "react";
import { useDropzone } from "react-dropzone";

const baseStyle = {
  flex: 1,
  display: "flex",
  flexDirection: "column",
  alignItems: "center",
  padding: "20px",
  borderWidth: 2,
  borderRadius: 20,
  borderColor: "#26C2E7",
  borderStyle: "dashed",
  backgroundColor: "#fafafa",
  color: "#c4c4c4",
  outline: "none",
  transition: "border .24s ease-in-out"
};

const activeStyle = {
  borderColor: "#f2f"
};

const acceptStyle = {
  borderColor: "#f8f"
};

const rejectStyle = {
  borderColor: "#f2f"
};
function InputFiles(props) {
  const [files, setFiles] = useState({});
  const {
    fileRejections,
    isDragActive,
    isDragAccept,
    isDragReject,
    getRootProps,
    getInputProps
  } = useDropzone({
    onDrop: (acceptedFiles) => {
      setFiles((prevFiles) =>
        acceptedFiles.reduce(
          (acc, file) => ({
            ...acc,
            [file.name]: {
              file,
              fileType: ""
            }
          }),
          prevFiles
        )
      );
    },
    accept: ".xlsx,.docx,.pdf"
  });
  const style = useMemo(
    () => ({
      ...baseStyle,
      ...(isDragActive ? activeStyle : {}),
      ...(isDragAccept ? acceptStyle : {}),
      ...(isDragReject ? rejectStyle : {})
    }),
    [isDragActive, isDragReject, isDragAccept]
  );
  const acceptedFileItems = Object.keys(files).map((fileName) => {
    const currentFile = files[fileName].file;
    const onSelectChange = (e) => {
      e.persist();
      setFiles((prevFiles) => {
        return {
          ...prevFiles,
          [fileName]: {
            ...prevFiles[fileName],
            fileType: e.target.value
          }
        };
      });
    };

    return (
      <li key={fileName}>
        <div style={{ display: "flex" }}>
          <span>
            {currentFile.path} - {currentFile.size} bytes
          </span>
          <select value={currentFile.fileType} onChange={onSelectChange}>
            <option value=""></option>
            <option value="summary">summary</option>
            <option value="description">report</option>
            <option value="report">description</option>
          </select>
        </div>
      </li>
    );
  });

  const fileRejectionItems = fileRejections.map(({ file, errors }) => (
    <li key={file.path}>
      {file.path} - {file.size} bytes
      <ul>
        {errors.map((e) => (
          <li key={e.code}>{e.message}</li>
        ))}
      </ul>
    </li>
  ));

  return (
    <section className="container">
      {/* <div {...getRootProps({ style })}> */}
      <div {...getRootProps({ style })}>
        <input {...getInputProps()} />
        <p>Drag 'n' drop some files here, or click to select files</p>
        <em>(Only *.pdf , *.xlsx , *.docx files will be accepted)</em>
      </div>
      <aside>
        <h4>Accepted files</h4>
        <ul>{acceptedFileItems}</ul>
        <h4>Rejected files</h4>
        <ul>{fileRejectionItems}</ul>
        <button onClick={() => console.log(files)}>console log files</button>
      </aside>
    </section>
  );
}

export default InputFiles;

你可以在这里查看它的工作情况https://codesandbox.io/s/react-drop-zone-select-vhc2l