React.js 文件上传 UI 拖放不工作

Question

我正在尝试为我的 react.js 应用编写文件上传。但是，我无法使拖放区正常工作。即使我停止传播并阻止拖放事件的默认设置，它仍然无法按预期工作。浏览器仍然打开我的文件。

export default function DraggableUploader() {

    const fileInput = useRef(null)
    const [loadedFile, setLoadedFile] = useState(null)
    const [isLoading, setIsLoading] = useState(false)

    const handleDragEnter = e => {
        e.preventDefault();
        e.stopPropagation();
      };
    const handleDragLeave = e => {
        e.preventDefault();
        e.stopPropagation();
    };
    const handleDragOver = e => {
        e.preventDefault();
        e.stopPropagation();
    };
    const handleDrop = e => {
        e.preventDefault();
        e.stopPropagation();

    };


    function handleSubmit(e) {
        e.preventDefault()
        console.log(`current file`, loadedFile.name)



    }

    return (
        <div className="dropzone">
            <div className="sub-header">Drag your audio file here:</div>
            <div className="draggable-container">
                <input 
                    type="file" 
                    className="file-browser-input"
                    name="file-browser-input"
                    style={{display: "none"}}
                    ref={fileInput} 
                    onDrop={e => handleDrop(e)}
                    onDragOver={e => handleDragOver(e)}
                    onDragEnter={e => handleDragEnter(e)}
                    onDragLeave={e => handleDragLeave(e)}
                    onChange={handleInputChange}  
                />


                <div className="file-browser-container">
                    <Button variant="outline-primary" onClick={handleInputClick}>Browse</Button>

                </div>

            </div>
            <Button variant="primary" onClick={handleSubmit}>Submit</Button>
        </div>
    )
}

Answer 1

显然我没有 useEffect 来添加事件侦听器。如果您添加以下代码，一切都会按预期工作：

useEffect(() => {
        let div = dropRef.current;
        div.addEventListener('dragenter', handleDragEnter);
        div.addEventListener('dragleave', handleDragLeave);
        div.addEventListener('dragover', handleDragOver);
        div.addEventListener('drop', handleDrop);
        return function cleanup() {
          div.removeEventListener('dragenter', handleDragEnter);
          div.removeEventListener('dragleave', handleDragLeave);
          div.removeEventListener('dragover', handleDragOver);
          div.removeEventListener('drop', handleDrop);
        };
      });

Answer 2

如果您使用箭头函数，则无需附加事件侦听器。使用下面的代码，所有事件都会起作用我在上面的代码中看到的唯一问题是你将事件附加到隐藏的输入上，将事件附加到最外面 div 它会起作用。祝你好运！

export default function App() {

  const handleDragEnter = e => {
    e.preventDefault();
    console.log("drag enter");
  };

  const handleDragLeave = e => {
    e.preventDefault();
    console.log("drag leave");
  };

  const handleDragOver = e => {
    e.preventDefault();
    console.log("drag over");
  };

  const handleDrop = e => {
    e.preventDefault();
    console.log("drag drop");
  };

  const handleInputChange = () => {};

  return (
    <div
      className="dropzone"
      onDrop={e => handleDrop(e)}
      onDragOver={e => handleDragOver(e)}
      onDragEnter={e => handleDragEnter(e)}
      onDragLeave={e => handleDragLeave(e)}
      onChange={handleInputChange}
    >
      <div className="sub-header">Drag your audio file here:</div>
      <div className="draggable-container">
        <input
          type="file"
          className="file-browser-input"
          name="file-browser-input"
          style={{ display: "none" }}
        />
      </div>
    </div>
  );
}

React.js 文件上传 UI 拖放不工作

React.js file upload UI drag and drop not working

javascript

drag-and-drop

input

dom-events

reactjs