text: import React, {createElement, PureComponent} from 'react';
  import pathToRegexp from 'path-to-regexp';
  import {Breadcrumb} from 'antd';
  import styles from './index.less';
  import {urlToList} from '../_utils/pathTools';
  
  export const getBreadcrumb = (breadcrumbNameMap, url) => {
    let breadcrumb = breadcrumbNameMap[url];
    if (!breadcrumb) {
      Object.keys(breadcrumbNameMap).forEach(item => {
        if (pathToRegexp(item).test(url)) {
          breadcrumb = breadcrumbNameMap[item];
        }
      });
    }
    return breadcrumb || {};
  };
  
  export default class BreadcrumbView extends PureComponent {
    state = {
      breadcrumb: null,
    };
  
    componentDidMount() {
      this.getBreadcrumbDom();
    }
  
    componentDidUpdate(preProps) {
      const { location } = this.props;
      if (!location || !preProps.location) {
        return;
      }
      const prePathname = preProps.location.pathname;
      if (prePathname !== location.pathname) {
        this.getBreadcrumbDom();
      }
    }
  
    getBreadcrumbDom = () => {
      const breadcrumb = this.conversionBreadcrumbList();
      this.setState({
        breadcrumb,
      });
    };
  
    getBreadcrumbProps = () => {
      const { routes, params, location, breadcrumbNameMap } = this.props;
      return {
        routes,
        params,
        routerLocation: location,
        breadcrumbNameMap,
      };
    };
  
    // Generated according to props
    conversionFromProps = () => {
      const { breadcrumbList, breadcrumbSeparator, itemRender, linkElement = 'a' } = this.props;
      return (
        <Breadcrumb className={styles.breadcrumb} separator={breadcrumbSeparator}>
          {breadcrumbList.map(item => {
            const title = itemRender ? itemRender(item) : item.title;
            return (
              <Breadcrumb.Item key={item.title}>
                {item.href
                  ? createElement(
                      linkElement,
                      {
                        [linkElement === 'a' ? 'href' : 'to']: item.href,
                      },
                      title
                    )
                  : title}
              </Breadcrumb.Item>
            );
          })}
        </Breadcrumb>
      );
    };
  
    conversionFromLocation = (routerLocation, breadcrumbNameMap) => {
      const { breadcrumbSeparator, home, itemRender, linkElement = 'a' } = this.props;
      // Convert the url to an array
      const pathSnippets = urlToList(routerLocation.pathname);
      // Loop data mosaic routing
      const extraBreadcrumbItems = pathSnippets.map((url, index) => {
        const currentBreadcrumb = getBreadcrumb(breadcrumbNameMap, url);
        if (currentBreadcrumb.inherited) {
          return null;
        }
        const isLinkable = index !== pathSnippets.length - 1 && currentBreadcrumb.component;
        const name = itemRender ? itemRender(currentBreadcrumb) : currentBreadcrumb.name;
        return currentBreadcrumb.name && !currentBreadcrumb.hideInBreadcrumb ? (
          <Breadcrumb.Item key={url}>
            {createElement(
              isLinkable ? linkElement : 'span',
              { [linkElement === 'a' ? 'href' : 'to']: url },
              name
            )}
          </Breadcrumb.Item>
        ) : null;
      });
      // Add home breadcrumbs to your head
      extraBreadcrumbItems.unshift(
        <Breadcrumb.Item key="home">
          {createElement(
            linkElement,
            {
              [linkElement === 'a' ? 'href' : 'to']: '/',
            },
            home || 'Home'
          )}
        </Breadcrumb.Item>
      );
      return (
        <Breadcrumb className={styles.breadcrumb} separator={breadcrumbSeparator}>
          {extraBreadcrumbItems}
        </Breadcrumb>
      );
    };
  
    /**
     * 将参数转化为面包屑
     * Convert parameters into breadcrumbs
     */
    conversionBreadcrumbList = () => {
      const { breadcrumbList, breadcrumbSeparator } = this.props;
      const { routes, params, routerLocation, breadcrumbNameMap } = this.getBreadcrumbProps();
      if (breadcrumbList && breadcrumbList.length) {
        return this.conversionFromProps();
      }
      // 如果传入 routes 和 params 属性
      // If pass routes and params attributes
      if (routes && params) {
        return (
          <Breadcrumb
            className={styles.breadcrumb}
            routes={routes.filter(route => route.breadcrumbName)}
            params={params}
            itemRender={this.itemRender}
            separator={breadcrumbSeparator}
          />
        );
      }
      // 根据 location 生成 面包屑
      // Generate breadcrumbs based on location
      if (routerLocation && routerLocation.pathname) {
        return this.conversionFromLocation(routerLocation, breadcrumbNameMap);
      }
      return null;
    };
  
    // 渲染Breadcrumb 子节点
    // Render the Breadcrumb child node
    itemRender = (route, params, routes, paths) => {
      const { linkElement = 'a' } = this.props;
      const last = routes.indexOf(route) === routes.length - 1;
      return last || !route.component ? (
        <span>{route.breadcrumbName}</span>
      ) : (
        createElement(
          linkElement,
          {
            href: paths.join('/') || '/',
            to: paths.join('/') || '/',
          },
          route.breadcrumbName
        )
      );
    };
  
    render() {
      const { breadcrumb } = this.state;
      return breadcrumb;
    }
  }
  