我需要根據ListView標題的點擊對ListView上的內容進行排序。我正在使用C++/CLI,因此我得到this Microsoft article並使用C++/CLI對其進行編碼。點擊標題時排序ListView
這裏是我的結果:
ListViewColumnSorter.h
/// <summary>
/// This class is an implementation of the 'IComparer' interface.
/// </summary>
#pragma once
public ref class ListViewColumnSorter : System::Collections::IComparer
{
public:
ListViewColumnSorter();
virtual int Compare(System::Object^ x, System::Object^ y);
private:
/// <summary>
/// Specifies the column to be sorted
/// </summary>
int ColumnToSort;
/// <summary>
/// Specifies the order in which to sort (i.e. 'Ascending').
/// </summary>
System::Windows::Forms::SortOrder OrderOfSort;
/// <summary>
/// Case insensitive comparer object
/// </summary>
System::Collections::CaseInsensitiveComparer^ ObjectCompare;
property int SortColumn;
property System::Windows::Forms::SortOrder SortOrder;
};
ListViewColumnSorter.cpp
/// <summary>
/// This class is an implementation of the 'IComparer' interface.
/// </summary>
#include "ListViewColumnSorter.h"
ListViewColumnSorter::ListViewColumnSorter()
{
// Initialize the column to '0'
ColumnToSort = 0;
// Initialize the sort order to 'none'
OrderOfSort = System::Windows::Forms::SortOrder::None;
// Initialize the CaseInsensitiveComparer object
ObjectCompare = gcnew System::Collections::CaseInsensitiveComparer();
}
/// <summary>
/// This method is inherited from the IComparer interface. It compares the two objects passed using a case insensitive comparison.
/// </summary>
/// <param name="x">First object to be compared</param>
/// <param name="y">Second object to be compared</param>
/// <returns>The result of the comparison. "0" if equal, negative if 'x' is less than 'y' and positive if 'x' is greater than 'y'</returns>
int ListViewColumnSorter::Compare(System::Object^ x, System::Object^ y)
{
int compareResult;
System::Windows::Forms::ListViewItem^ listviewX, listviewY;
// Cast the objects to be compared to ListViewItem objects
listviewX = (System::Windows::Forms::ListViewItem^) x; <--- ERROR HERE
listviewY = (System::Windows::Forms::ListViewItem^) y; <--- ERROR HERE
// Compare the two items
compareResult = ObjectCompare->Compare(listviewX->SubItems[ColumnToSort].Text,
listviewY->SubItems[ColumnToSort].Text);
// Calculate correct return value based on object comparison
if (OrderOfSort == System::Windows::Forms:: SortOrder::Ascending)
{
// Ascending sort is selected, return normal result of compare operation
return compareResult;
}
else if (OrderOfSort == System::Windows::Forms::SortOrder::Descending)
{
// Descending sort is selected, return negative result of compare operation
return (-compareResult);
}
else
{
// Return '0' to indicate they are equal
return 0;
}
}
/// <summary>
/// Gets or sets the number of the column to which to apply the sorting operation (Defaults to '0').
/// </summary>
void ListViewColumnSorter::SortColumn::set(int value)
{
ColumnToSort = value;
}
int ListViewColumnSorter::SortColumn::get()
{
return ColumnToSort;
}
/// <summary>
/// Gets or sets the order of sorting to apply (for example, 'Ascending' or 'Descending').
/// </summary>
void ListViewColumnSorter::SortOrder::set(System::Windows::Forms::SortOrder value)
{
OrderOfSort = value;
}
System::Windows::Forms::SortOrder ListViewColumnSorter::SortOrder::get()
{
return OrderOfSort;
}
I'm有編譯這段代碼有問題,上功能比較,我無法將ListViewItem ^轉換爲listviewX和listviewY以獲取其str荷蘭國際集團(檢查代碼標記):
表達必須有解決這一問題所需要的類類型
建議。
https://msdn.microsoft.com/en-us/library/1bh3t52k.aspx –