如何：向 ListView 控件添加搜索功能
通常，在 ListView 控件中使用大型项列表时，需要向用户提供搜索功能。 ListView 控件通过两种方法提供此功能：文本匹配和位置搜索。
给定搜索字符串和可选的开始和结束索引时，利用 FindItemWithText 方法可在列表视图或详细信息视图中对 ListView 执行文本搜索。 而在给定一组 x 和 y 坐标以及搜索方向的情况下，利用 FindNearestItem 方法可在图标视图或平铺视图中查找 ListView 中的项。
使用文本查找项
调用 FindItemWithText 方法，传递要查找的项的文本。
下面的代码示例演示如何创建一个基本的 ListView，使用项填充它，并用用户的文本输入来查找列表中的项。
private:
ListView^ textListView;
TextBox^ searchBox;
private:
void InitializeTextSearchListView()
{
textListView = gcnew ListView();
searchBox = gcnew TextBox();
searchBox->Location = Point(150, 20);
textListView->Scrollable = true;
textListView->Width = 100;
// Set the View to list to use the FindItemWithText method.
textListView->View = View::List;
// Populate the ListViewWithItems
textListView->Items->AddRange(gcnew array<ListViewItem^>{
gcnew ListViewItem("Amy Alberts"),
gcnew ListViewItem("Amy Recker"),
gcnew ListViewItem("Erin Hagens"),
gcnew ListViewItem("Barry Johnson"),
gcnew ListViewItem("Jay Hamlin"),
gcnew ListViewItem("Brian Valentine"),
gcnew ListViewItem("Brian Welker"),
gcnew ListViewItem("Daniel Weisman") });
// Handle the TextChanged to get the text for our search.
searchBox->TextChanged += gcnew EventHandler(this,
&Form1::searchBox_TextChanged);
// Add the controls to the form.
this->Controls->Add(textListView);
this->Controls->Add(searchBox);
}
private:
void searchBox_TextChanged(Object^ sender, EventArgs^ e)
{
// Call FindItemWithText with the contents of the textbox.
ListViewItem^ foundItem =
textListView->FindItemWithText(searchBox->Text, false, 0, true);
if (foundItem != nullptr)
{
textListView->TopItem = foundItem;
}
}
private ListView textListView = new ListView();
private TextBox searchBox = new TextBox();
private void InitializeTextSearchListView()
{
searchBox.Location = new Point(10, 60);
textListView.Scrollable = true;
textListView.Width = 80;
textListView.Height = 50;
// Set the View to list to use the FindItemWithText method.
textListView.View = View.List;
// Populate the ListViewWithItems
textListView.Items.AddRange(new ListViewItem[]{
new ListViewItem("Amy Alberts"),
new ListViewItem("Amy Recker"),
new ListViewItem("Erin Hagens"),
new ListViewItem("Barry Johnson"),
new ListViewItem("Jay Hamlin"),
new ListViewItem("Brian Valentine"),
new ListViewItem("Brian Welker"),
new ListViewItem("Daniel Weisman") });
// Handle the TextChanged to get the text for our search.
searchBox.TextChanged += new EventHandler(searchBox_TextChanged);
// Add the controls to the form.
this.Controls.Add(textListView);
this.Controls.Add(searchBox);
}
private void searchBox_TextChanged(object sender, EventArgs e)
{
// Call FindItemWithText with the contents of the textbox.
ListViewItem foundItem =
textListView.FindItemWithText(searchBox.Text, false, 0, true);
if (foundItem != null)
{
textListView.TopItem = foundItem;
}
}
Private textListView As New ListView()
Private WithEvents searchBox As New TextBox()
Private Sub InitializeTextSearchListView()
searchBox.Location = New Point(150, 20)
textListView.Scrollable = True
textListView.Width = 80
textListView.Height = 50
' Set the View to list to use the FindItemWithText method.
textListView.View = View.List
' Populate the ListView with items.
textListView.Items.AddRange(New ListViewItem() { _
New ListViewItem("Amy Alberts"), _
New ListViewItem("Amy Recker"), _
New ListViewItem("Erin Hagens"), _
New ListViewItem("Barry Johnson"), _
New ListViewItem("Jay Hamlin"), _
New ListViewItem("Brian Valentine"), _
New ListViewItem("Brian Welker"), _
New ListViewItem("Daniel Weisman")})
' Add the controls to the form.
Me.Controls.Add(textListView)
Me.Controls.Add(searchBox)
End Sub
Private Sub searchBox_TextChanged(ByVal sender As Object, ByVal e As EventArgs) _
Handles searchBox.TextChanged
' Call FindItemWithText with the contents of the textbox.
Dim foundItem As ListViewItem = _
textListView.FindItemWithText(searchBox.Text, False, 0, True)
If (foundItem IsNot Nothing) Then
textListView.TopItem = foundItem
End If
End Sub
使用 x 坐标和 y 坐标查找项
创建一个 ListView，其中 View 属性设置为 SmallIcon 或 LargeIcon，然后用项填充 ListView。
调用 FindNearestItem 方法，传递所需的 x 坐标和 y 坐标以及要搜索的方向。
下面的代码示例演示如何创建基本图标 ListView，用项填充它，并捕获 MouseDown 事件，以朝上查找最近的项。
ListView^ iconListView;
TextBox^ previousItemBox;
private:
void InitializeLocationSearchListView()
{
previousItemBox = gcnew TextBox();
iconListView = gcnew ListView();
previousItemBox->Location = Point(150, 20);
// Create an image list for the icon ListView.
iconListView->SmallImageList = gcnew ImageList();
// Add an image to the ListView small icon list.
iconListView->SmallImageList->Images->Add(
gcnew Bitmap(Control::typeid, "Edit.bmp"));
// Set the view to small icon and add some items with the image
// in the image list.
iconListView->View = View::SmallIcon;
iconListView->Items->AddRange(gcnew array<ListViewItem^>{
gcnew ListViewItem("Amy Alberts", 0),
gcnew ListViewItem("Amy Recker", 0),
gcnew ListViewItem("Erin Hagens", 0),
gcnew ListViewItem("Barry Johnson", 0),
gcnew ListViewItem("Jay Hamlin", 0),
gcnew ListViewItem("Brian Valentine", 0),
gcnew ListViewItem("Brian Welker", 0),
gcnew ListViewItem("Daniel Weisman", 0) });
this->Controls->Add(iconListView);
this->Controls->Add(previousItemBox);
// Handle the MouseDown event to capture user input.
iconListView->MouseDown += gcnew MouseEventHandler(
this, &Form1::iconListView_MouseDown);
}
void iconListView_MouseDown(Object^ sender, MouseEventArgs^ e)
{
// Find the next item up from where the user clicked.
ListViewItem^ foundItem = iconListView->FindNearestItem(
SearchDirectionHint::Up, e->X, e->Y);
// Display the results in a textbox..
if (foundItem != nullptr)
{
previousItemBox->Text = foundItem->Text;
}
else
{
previousItemBox->Text = "No item found";
}
}
ListView iconListView = new ListView();
TextBox previousItemBox = new TextBox();
private void InitializeLocationSearchListView()
{
previousItemBox.Location = new Point(150, 20);
// Create an image list for the icon ListView.
iconListView.LargeImageList = new ImageList();
iconListView.Height = 400;
// Add an image to the ListView large icon list.
iconListView.LargeImageList.Images.Add(
new Bitmap(typeof(Control), "Edit.bmp"));
// Set the view to large icon and add some items with the image
// in the image list.
iconListView.View = View.LargeIcon;
iconListView.Items.AddRange(new ListViewItem[]{
new ListViewItem("Amy Alberts", 0),
new ListViewItem("Amy Recker", 0),
new ListViewItem("Erin Hagens", 0),
new ListViewItem("Barry Johnson", 0),
new ListViewItem("Jay Hamlin", 0),
new ListViewItem("Brian Valentine", 0),
new ListViewItem("Brian Welker", 0),
new ListViewItem("Daniel Weisman", 0) });
this.Controls.Add(iconListView);
this.Controls.Add(previousItemBox);
// Handle the MouseDown event to capture user input.
iconListView.MouseDown +=
new MouseEventHandler(iconListView_MouseDown);
//iconListView.MouseWheel += new MouseEventHandler(iconListView_MouseWheel);
}
void iconListView_MouseDown(object sender, MouseEventArgs e)
{
// Find the an item above where the user clicked.
ListViewItem foundItem =
iconListView.FindNearestItem(SearchDirectionHint.Up, e.X, e.Y);
// Display the results in a textbox..
if (foundItem != null)
previousItemBox.Text = foundItem.Text;
else
previousItemBox.Text = "No item found";
}
Private WithEvents iconListView As New ListView()
Private previousItemBox As New TextBox()
Private Sub InitializeLocationSearchListView()
previousItemBox.Location = New Point(150, 20)
' Create an image list for the icon ListView.
iconListView.LargeImageList = New ImageList()
' Add an image to the ListView large icon list.
iconListView.LargeImageList.Images.Add(New Bitmap(GetType(Control), "Edit.bmp"))
' Set the view to large icon and add some items with the image
' in the image list.
iconListView.View = View.SmallIcon
iconListView.Items.AddRange(New ListViewItem() { _
New ListViewItem("Amy Alberts", 0), _
New ListViewItem("Amy Recker", 0), _
New ListViewItem("Erin Hagens", 0), _
New ListViewItem("Barry Johnson", 0), _
New ListViewItem("Jay Hamlin", 0), _
New ListViewItem("Brian Valentine", 0), _
New ListViewItem("Brian Welker", 0), _
New ListViewItem("Daniel Weisman", 0)})
Me.Controls.Add(iconListView)
Me.Controls.Add(previousItemBox)
End Sub
Sub iconListView_MouseDown(ByVal sender As Object, ByVal e As MouseEventArgs) _
Handles iconListView.MouseDown
' Find the next item up from where the user clicked.
Dim foundItem As ListViewItem = _
iconListView.FindNearestItem(SearchDirectionHint.Up, e.X, e.Y)
' Display the results in a textbox.
If (foundItem IsNot Nothing) Then
previousItemBox.Text = foundItem.Text
Else
previousItemBox.Text = "No item found"
End If
End Sub
