如何在數據綁定模式下按降序對ListBox進行排序？

Question

如何在數據綁定模式下按降序對ListBox進行排序？

我舉一個例子：

System.Drawing.Printing.PrintDocument printDoc = new System.Drawing.Printing.PrintDocument(); 
ArrayList paperSizes = new ArrayList(); 

for (int i = 0; i < printDoc.PrinterSettings.PaperSizes.Count; i++) 
{ 
    paperSizes.Add(printDoc.PrinterSettings.PaperSizes[i]); 
} 

listBox1.DataSource = paperSizes; 
listBox1.DisplayMember = "PaperName"; 
listBox1.ValueMember = "Kind"; 

Answer 1

你可以試試這個代碼：

private void SortListBoxItems(ref ListBox lb) 
{ 
    List<object> items; 
    items = lb.Items.OfType<object>().ToList(); 
    lb.Items.Clear(); 
    lb.Items.AddRange(items.OrderByDescending(i => i).ToArray()); 
} 

Answer 2

使用paperSizes.sort（paperSizes）;

System.Drawing.Printing.PrintDocument printDoc = new System.Drawing.Printing.PrintDocument(); 
ArrayList paperSizes = new ArrayList(); 

for (int i = 0; i < printDoc.PrinterSettings.PaperSizes.Count; i++) 
{ 
    paperSizes.Add(printDoc.PrinterSettings.PaperSizes[i]); 
} 
paperSizes.sort(); 
listBox1.DataSource = paperSizes; 
listBox1.DisplayMember = "PaperName"; 
listBox1.ValueMember = "Kind"; 

Answer 3

我還沒有建設性的答案和優雅的解決方案呢。但是在Rai和NicoRiff的幫助下，我意識到我們不能在數據綁定模式上做更多的事情，可能我應該在數據綁定之前進行排序。我獲得的另一件事是我應該把嘗試和捕捉，以避免無聲的崩潰，並提供錯誤信息，以防在數據綁定模式下意外調用ListBox.Sorted = true或ListBox.Items.Add方法。

1. In Rai's code sample, when we call paperSizes.sort(), VS catch error "Failed to compare two elements in the array." 
2. in Nico's code sample, because ListBox is on data-binding mode, VS will raise an error "Items collection cannot be modified when the DataSource property is set."