c# - 使用 Item 对 ListView 进行排序，然后 - 子项目 1

Question

我想像这样对我的项目和子项目进行排序：

one - a
one - b
one - c
three - apricot
three - banana
two - orange
two - pear

我已将排序设置为升序，但这仅对第一列进行排序。

Answer 1

您需要使用该ListView.ListViewItemSorter属性来提供自定义IComparer. 您可以访问方法中的ListViewItem及其子项Compare。

这是一个这样做的例子（快速组合在一起）。请注意代码中解释什么部分只是设置示例的注释ListView。实际实现您想要的排序所需的代码很少，我已经用注释标记了它们所在的位置。我所做的唯一不在代码中的设置是ListView在一个新的空白 WinForm 上放置一个；其余的在代码中完成，下面有一个示例图像显示了结果。

using System;
using System.Collections.Generic;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace WindowsFormsApplication1
{
  public partial class Form1 : Form
  {
    public Form1()
    {
      InitializeComponent();
      this.SuspendLayout();

      // This part is just setting up the ListView 
      // Turn off default sorting, and set to display columns
      this.listView1.Sorting = SortOrder.None;
      this.listView1.View = View.Details;

      // Add two columns (ColumnA and ColumnB)
      this.listView1.Columns.Add(new ColumnHeader());
      this.listView1.Columns[0].Width = 100;
      this.listView1.Columns[0].Text = "ColumnA";
      this.listView1.Columns.Add(new ColumnHeader());
      this.listView1.Columns[1].Width = 100;
      this.listView1.Columns[1].Text = "ColumnB";

      // Add the actual column information
      ListViewItem listViewItem1 = new ListViewItem(new String[] {"three", "banana"});
      ListViewItem listViewItem2 = new ListViewItem(new String[] {"one", "c"});
      ListViewItem listViewItem3 = new ListViewItem(new String[] {"one", "b"});
      ListViewItem listViewItem4 = new ListViewItem(new String[] {"three", "apricot"});
      this.listView1.Items.AddRange(new ListViewItem[]{listViewItem1, 
                                                       listViewItem2, 
                                                       listViewItem3, 
                                                       listViewItem4});

      /*
         Now the actual sorting - this next line makes it sort using 
         the custom comparer we've defined. Assigning a new IComparer
         automatically sorts using it.
      */
      this.listView1.ListViewItemSorter = new ListViewItemComparer();

      this.ResumeLayout(false);
    }
  }

  // Implements the manual sorting of items by columns. 
  class ListViewItemComparer : IComparer  
  {
    public ListViewItemComparer()
    {

    }

    // This function actually does the comparison     
    public int Compare(object x, object y)
    {
      /* 
         We need to access the same item multiple times, so
         save a local reference to reduce typecasting over and
         over again
      */
      ListViewItem FirstItem = (ListViewItem) x;
      ListViewItem SecondItem = (ListViewItem) y;

      /* 
         Compare the two columns of each item, combined to make 
         a single item for comparing.
      */
      return String.Compare(FirstItem.SubItems[0].Text + FirstItem.SubItems[1].Text,
                            SecondItem.SubItems[0].Text + SecondItem.SubItems[1].Text);
    }
  }
}

运行上述代码的结果（注意项目的添加顺序不同）：