I am trying to create a table component where the component will serve some special className to its specific children.

    const BasicTable = ({ children }) => {
        const RenderChild = Children.map(children, (el) => {
            const child = el;
    
            if (child !== null) {
                if (child.props.originalType !== "th") {
                    return <child.type {...child.props} className="th" />;
                }
    
                return <child.type {...child.props} />;
            }
            return null;
        });
    
        return (
            <div className="table-responsive">
                <table className="table w-full bg-transparent">{RenderChild}</table>
            </div>
        );
    };

This is my component and I want to use it like this.

    <BasicTable>
        <thead>
            <tr>
                <th>ID</th>
                <th>Name</th>
                <th>Position</th>
                <th>Salary</th>
            </tr>
        </thead>
        <tbody>
            <tr>
                <td>dsfa</td>
                <td>dsfa</td>
                <td>dsfa</td>
                <td>dsfa</td>
            </tr>
        </tbody>
    </BasicTable>

But here the problem is my Children.map function only loop through its immediate children. How do I pass props to its nested child (th, td, ...etc)

CodePudding user response：

You can define a recursive function to iterate over all the children until thi child is null or is of type string or any other condition based on your requirement, here is an example:

const BasicTable = ({ children }) => {

  const iterateOverChildren = (children) => {
    return React.Children.map(children, (child) => {
      // equal to (if (child == null || typeof child == 'string'))
      if (!React.isValidElement(child)) return child;

      return React.cloneElement(child, {
        ...child.props,
        // you can alse read child original className by child.props.className
        className: child.type == 'th' ? 'th' : '',
        children: iterateOverChildren(child.props.children)})
    })
  };

  return (
    <div className="table-responsive">
      <table className="table w-full bg-transparent">
        {iterateOverChildren(children)}
      </table>
    </div>
  );
};

function App() {
  return (
      <BasicTable>
        <thead>
          <tr>
            <th>ID</th>
            <th>Name</th>
            <th>Position</th>
            <th>Salary</th>
          </tr>
        </thead>
        <tbody>
          <tr>
            <td>dsfa</td>
            <td>dsfa</td>
            <td>dsfa</td>
            <td>dsfa</td>
          </tr>
        </tbody>
      </BasicTable>
  );
}


ReactDOM.render(<App/>, document.getElementById('root'))

.th{
  color: green;
}

<script src="https://cdnjs.cloudflare.com/ajax/libs/react/17.0.2/umd/react.production.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react-dom/17.0.2/umd/react-dom.production.min.js"></script>

<div id="root"></div>

CodePudding user response：

You can provide children prop after applying the classNames to the current child. You can define another function to apply custom class names as per your needs (The logic can be changed as per your needs).

This would also work.

import { Children, isValidElement } from "react";

const BasicTable = ({ children }) => {
  const RenderChild = (children) => {
    return Children.map(children, (child) => {
      if (isValidElement(child)) {
        return (
          <child.type
            {...child.props}
            children={RenderChild(child.props.children)}
            className={resolveCalssName(child.type)}
          />
        );
      }
      // non react elements (text inside the table ...etc)
      return child;
    });
  };

  const resolveCalssName = (type) => {
    switch (type) {
      case "thead":
        return "custom-thead-class-name";
      case "tbody":
        return "custom-tbody-class-name";
      case "tr":
        return "custom-tr-class-name";
      case "th":
        return "custom-th-class-name";
      case "td":
        return "custom-td-class-name";
      default:
        return "";
    }
  };

  return (
    <div className="table-responsive">
      <table className="table w-full bg-transparent">
        {RenderChild(children)}
      </table>
    </div>
  );
};

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