javascript - ReactJS:未知类型的参数不可分配给来自文件读取器的 SetStateAction<string> 类型的参数

Question

我想知道为什么我的代码无法工作并导致我出现此错误 Argument of type 'unknown' is not assignable to parameter of type 'SetStateAction<string>'. Type 'unknown' is not assignable to type '(prevState: string) => string'.ts(2345) .

此错误来自此代码 setBaseImage(base64);这个函数的作用:

    const uploadImage = async (e: any) => {
    const file = e.target.files[0];
    const base64 = await convertBase64(file);
    setBaseImage(base64);
  };

当前代码:

    const [baseImage, setBaseImage] = useState("");
const convertBase64 = (file: any) => {
    return new Promise((resolve, reject) => {
      const fileReader = new FileReader();
      fileReader.readAsDataURL(file);

      fileReader.onload = () => {
        resolve(fileReader.result);
      };

      fileReader.onerror = (error) => {
        reject(error);
      };
    });
  };

我只是按照这个教程source of the code

Answer 1

已经通过更新这行代码解决了问题:

setBaseImage(String(base64));