对数组和索引进行排序

Sorting arrays and indexes

本文关键字:排序 索引 数组      更新时间:2023-09-26

我在对固定数据表进行排序时遇到问题。我尝试使用此示例:https://github.com/facebook/fixed-data-table/blob/master/examples/old/SortExample.js

当我第一次按名称降序排序时,它成功排序并将前两行带到这些值:

编号:11 姓名:玛丽

ID:1 姓名:玛丽

....

之后,我按名称升序排序,然后再次按名称降序排序。

它为前两列带来了这些值:

ID:1 姓名:玛丽

编号:11 姓名:玛丽

....

为什么它会更改同名值的索引?(编号:11 和 id:1)

我每次都需要相同的排序索引。问题是什么,我该如何解决?

var SortTypes = {
  ASC: 'ASC',
  DESC: 'DESC',
};
function renderDate(/*object*/ cellData) {
  return <span>{cellData.toLocaleString()}</span>;
}
var SortExample = React.createClass({
  getInitialState() {
    return {
      rows: [{"id":"1","name":"Mary"},{"id":"2","name":"Felix"},
                   {"id":"3","name":"Mary"},{"id":"4","name":"Felix"},
                   {"id":"5","name":"Mary"},{"id":"6","name":"Felix"},
                   {"id":"7","name":"Mary"},{"id":"8","name":"Felix"},
                   {"id":"9","name":"Mary"},{"id":"10","name":"Felix"},
                   {"id":"11","name":"Mary"},{"id":"12","name":"Felix"},
                   {"id":"13","name":"Mary"},{"id":"14","name":"Felix"},
                   {"id":"15","name":"Mary"},{"id":"16","name":"Felix"},
                   {"id":"17","name":"Mary"},{"id":"18","name":"Felix"} ,
                   {"id":"19","name":"Mary"},{"id":"20","name":"Felix"}],sortBy: 'id',
      sortDir: null,
    };
  },
  _rowGetter(rowIndex) {
    return this.state.rows[rowIndex];
  },
  _sortRowsBy(cellDataKey) {
    var sortDir = this.state.sortDir;
    var sortBy = cellDataKey;
    if (sortBy === this.state.sortBy) {
      sortDir = this.state.sortDir === SortTypes.ASC ? SortTypes.DESC : SortTypes.ASC;
    } else {
      sortDir = SortTypes.DESC;
    }
    var rows = this.state.rows.slice();
    rows.sort((a, b) => {
      var sortVal = 0;
      if (a[sortBy] > b[sortBy]) {
        sortVal = 1;
      }
      if (a[sortBy] < b[sortBy]) {
        sortVal = -1;
      }
      if (sortDir === SortTypes.DESC) {
        sortVal = sortVal * -1;
      }
      return sortVal;
    });
    this.setState({
      rows,
      sortBy,
      sortDir,
    });
  },
  _renderHeader(label, cellDataKey) {
    return (
      <a onClick={this._sortRowsBy.bind(null, cellDataKey)}>{label}</a>
    );
  },
  render() {
    var sortDirArrow = '';
    if (this.state.sortDir !== null){
      sortDirArrow = this.state.sortDir === SortTypes.DESC ? ' ↓' : ' ↑';
    }
    return (
      <Table
        rowHeight={50}
        rowGetter={this._rowGetter}
        rowsCount={this.state.rows.length}
        headerHeight={50}
        width={1000}
        height={500}
        {...this.props}>
        <Column
          headerRenderer={this._renderHeader}
          label={'id' + (this.state.sortBy === 'id' ? sortDirArrow : '')}
          width={100}
          dataKey='id'
        />
        <Column
          headerRenderer={this._renderHeader}
          label={'First Name' + (this.state.sortBy === 'name' ? sortDirArrow : '')}
          width={200}
          dataKey='name'
        />
      </Table>
    );
  },
});




ReactDOM.render(
 <SortExample/>,
  document.getElementById('app')
)

对于稳定的排序,您需要更多排序参数,例如此解决方案,该参数首先按name排序,然后按id排序。

var rows = [{ "id": "1", "name": "Mary" }, { "id": "2", "name": "Felix" }, { "id": "3", "name": "Mary" }, { "id": "4", "name": "Felix" }, { "id": "5", "name": "Mary" }, { "id": "6", "name": "Felix" }, { "id": "7", "name": "Mary" }, { "id": "8", "name": "Felix" }, { "id": "9", "name": "Mary" }, { "id": "10", "name": "Felix" }, { "id": "11", "name": "Mary" }, { "id": "12", "name": "Felix" }, { "id": "13", "name": "Mary" }, { "id": "14", "name": "Felix" }, { "id": "15", "name": "Mary" }, { "id": "16", "name": "Felix" }, { "id": "17", "name": "Mary" }, { "id": "18", "name": "Felix" }, { "id": "19", "name": "Mary" }, { "id": "20", "name": "Felix" }];
rows.sort(function (a, b) {
    return a.name.localeCompare(b.name) || a.id - b.id;
});
document.write('<pre>' + JSON.stringify(rows, 0, 4) + '</pre>');