ListView.GetItemAt(Int32, Int32) Metode

Referensi

Definisi

Ruang nama:: System.Windows.Forms

Rakitan:: System.Windows.Forms.dll

Penting

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Mengambil item di lokasi yang ditentukan.

public:
 System::Windows::Forms::ListViewItem ^ GetItemAt(int x, int y);

public System.Windows.Forms.ListViewItem GetItemAt (int x, int y);

public System.Windows.Forms.ListViewItem? GetItemAt (int x, int y);

member this.GetItemAt : int * int -> System.Windows.Forms.ListViewItem

Public Function GetItemAt (x As Integer, y As Integer) As ListViewItem

Parameter

x: Int32

Koordinat x lokasi untuk mencari item (dinyatakan dalam koordinat klien).

y: Int32

Koordinat y lokasi untuk mencari item (dinyatakan dalam koordinat klien).

Mengembalikan

ListViewItem

ListViewItem yang mewakili item pada posisi yang ditentukan. Jika tidak ada item di lokasi yang ditentukan, metode akan mengembalikan null.

Contoh

Contoh kode berikut menunjukkan penggunaan PictureBox kontrol dan ListView . PictureBox diinisialisasi dengan mengatur PictureBox.BorderStyle properti dan PictureBox.SizeMode masing-masing menggunakan BorderStyle enumerasi dan PictureBoxSizeMode . diisi ListView dengan gambar dari direktori Sampel. Metode GetItemAt ini digunakan saat menangani ListView peristiwa kontrol MouseDown untuk menentukan apakah item dipilih. Jika item dipilih, penanganan aktivitas menampilkan file yang dipilih dengan mengatur PictureBox.Image properti . Contoh ini memerlukan keberadaan file JPG yang terletak di direktori C:\documents and Settings\All Users\Documents\My Pictures\Sample Pictures. Untuk menjalankan contoh ini, tempelkan kode ke dalam formulir dan panggil InitializePictureBox metode dan PopulateListView dalam konstruktor atau Load metode formulir. Pastikan semua peristiwa dikaitkan dengan penanganan aktivitas mereka.

private:
   void PopulateListView()
   {
      ListView1->Width = 270;
      ListView1->Location = System::Drawing::Point( 10, 10 );
      
      // Declare and construct the ColumnHeader objects.
      ColumnHeader^ header1;
      ColumnHeader^ header2;
      header1 = gcnew ColumnHeader;
      header2 = gcnew ColumnHeader;
      
      // Set the text, alignment and width for each column header.
      header1->Text = "File name";
      header1->TextAlign = HorizontalAlignment::Left;
      header1->Width = 70;
      header2->TextAlign = HorizontalAlignment::Left;
      header2->Text = "Location";
      header2->Width = 200;
      
      // Add the headers to the ListView control.
      ListView1->Columns->Add( header1 );
      ListView1->Columns->Add( header2 );
            
      // Specify that each item appears on a separate line.
      ListView1->View = View::Details;

      // Populate the ListView.Items property.
      // Set the directory to the sample picture directory.
      System::IO::DirectoryInfo^ dirInfo = gcnew System::IO::DirectoryInfo( "C:\\Documents and Settings\\All Users"
      "\\Documents\\My Pictures\\Sample Pictures" );
      
      // Get the .jpg files from the directory
      array<System::IO::FileInfo^>^files = dirInfo->GetFiles( "*.jpg" );
      
      // Add each file name and full name including path
      // to the ListView.
      if ( files != nullptr )
      {
         System::Collections::IEnumerator^ myEnum = files->GetEnumerator();
         while ( myEnum->MoveNext() )
         {
            System::IO::FileInfo^ file = safe_cast<System::IO::FileInfo^>(myEnum->Current);
            ListViewItem^ item = gcnew ListViewItem( file->Name );
            item->SubItems->Add( file->FullName );
            ListView1->Items->Add( item );
         }
      }
   }

   void InitializePictureBox()
   {
      PictureBox1 = gcnew PictureBox;
      
      // Set the location and size of the PictureBox control.
      this->PictureBox1->Location = System::Drawing::Point( 70, 120 );
      this->PictureBox1->Size = System::Drawing::Size( 140, 140 );
      this->PictureBox1->TabStop = false;
      
      // Set the SizeMode property to the StretchImage value.  This
      // will shrink or enlarge the image as needed to fit into
      // the PictureBox.
      this->PictureBox1->SizeMode = PictureBoxSizeMode::StretchImage;
      
      // Set the border style to a three-dimensional border.
      this->PictureBox1->BorderStyle = BorderStyle::Fixed3D;
      
      // Add the PictureBox to the form.
      this->Controls->Add( this->PictureBox1 );
   }

   void ListView1_MouseDown( Object^ /*sender*/, MouseEventArgs^ e )
   {
      ListViewItem^ selection = ListView1->GetItemAt( e->X, e->Y );
      
      // If the user selects an item in the ListView, display
      // the image in the PictureBox.
      if ( selection != nullptr )
      {
         PictureBox1->Image = System::Drawing::Image::FromFile( selection->SubItems[ 1 ]->Text );
      }
   }

private void PopulateListView()
{
    ListView1.Width = 270;
    ListView1.Location = new System.Drawing.Point(10, 10);

    // Declare and construct the ColumnHeader objects.
    ColumnHeader header1, header2;
    header1 = new ColumnHeader();
    header2 = new ColumnHeader();

    // Set the text, alignment and width for each column header.
    header1.Text = "File name";
    header1.TextAlign = HorizontalAlignment.Left;
    header1.Width = 70;

    header2.TextAlign = HorizontalAlignment.Left;
    header2.Text = "Location";
    header2.Width = 200;

    // Add the headers to the ListView control.
    ListView1.Columns.Add(header1);
    ListView1.Columns.Add(header2);

    // Specify that each item appears on a separate line.
    ListView1.View = View.Details;
    
    // Populate the ListView.Items property.
    // Set the directory to the sample picture directory.
    System.IO.DirectoryInfo dirInfo = 
        new System.IO.DirectoryInfo(
        "C:\\Documents and Settings\\All Users" +
        "\\Documents\\My Pictures\\Sample Pictures");

    // Get the .jpg files from the directory
    System.IO.FileInfo[] files = dirInfo.GetFiles("*.jpg");

    // Add each file name and full name including path
    // to the ListView.
    if (files != null)
    {
        foreach ( System.IO.FileInfo file in files )
        {
            ListViewItem item = new ListViewItem(file.Name);
            item.SubItems.Add(file.FullName);
            ListView1.Items.Add(item);
        }
    }
}

private void InitializePictureBox()
{
    PictureBox1 = new PictureBox();

    // Set the location and size of the PictureBox control.
    this.PictureBox1.Location = new System.Drawing.Point(70, 120);
    this.PictureBox1.Size = new System.Drawing.Size(140, 140);
    this.PictureBox1.TabStop = false;

    // Set the SizeMode property to the StretchImage value.  This
    // will shrink or enlarge the image as needed to fit into
    // the PictureBox.
    this.PictureBox1.SizeMode = PictureBoxSizeMode.StretchImage;

    // Set the border style to a three-dimensional border.
    this.PictureBox1.BorderStyle = BorderStyle.Fixed3D;

    // Add the PictureBox to the form.
    this.Controls.Add(this.PictureBox1);
}

private void ListView1_MouseDown(object sender, MouseEventArgs e)
{

    ListViewItem selection = ListView1.GetItemAt(e.X, e.Y);

    // If the user selects an item in the ListView, display
    // the image in the PictureBox.
    if (selection != null)
    {
        PictureBox1.Image = System.Drawing.Image.FromFile(
            selection.SubItems[1].Text);
    }
}

Private Sub PopulateListView()
    ListView1.Width = 270
    ListView1.Location = New System.Drawing.Point(10, 10)

    ' Declare and construct the ColumnHeader objects.
    Dim header1, header2 As ColumnHeader
    header1 = New ColumnHeader
    header2 = New ColumnHeader

    ' Set the text, alignment and width for each column header.
    header1.Text = "File name"
    header1.TextAlign = HorizontalAlignment.Left
    header1.Width = 70

    header2.TextAlign = HorizontalAlignment.Left
    header2.Text = "Location"
    header2.Width = 200

    ' Add the headers to the ListView control.
    ListView1.Columns.Add(header1)
    ListView1.Columns.Add(header2)

    ' Specify that each item appears on a separate line.
    ListView1.View = View.Details

    ' Populate the ListView.Items property.
    ' Set the directory to the sample picture directory.
    Dim dirInfo As New System.IO.DirectoryInfo _
        ("C:\Documents and Settings\All Users" _
        & "\Documents\My Pictures\Sample Pictures")
    Dim file As System.IO.FileInfo

    ' Get the .jpg files from the directory
    Dim files() As System.io.FileInfo = dirInfo.GetFiles("*.jpg")

    ' Add each file name and full name including path
    ' to the ListView.
    If (files IsNot Nothing) Then
        For Each file In files
            Dim item As New ListViewItem(file.Name)
            item.SubItems.Add(file.FullName)
            ListView1.Items.Add(item)
        Next
    End If
End Sub

Private Sub InitializePictureBox()
    PictureBox1 = New PictureBox

    ' Set the location and size of the PictureBox control.
    Me.PictureBox1.Location = New System.Drawing.Point(70, 120)
    Me.PictureBox1.Size = New System.Drawing.Size(140, 140)
    Me.PictureBox1.TabStop = False

    ' Set the SizeMode property to the StretchImage value.  This
    ' will shrink or enlarge the image as needed to fit into
    ' the PictureBox.
    Me.PictureBox1.SizeMode = PictureBoxSizeMode.StretchImage

    ' Set the border style to a three-dimensional border.
    Me.PictureBox1.BorderStyle = BorderStyle.Fixed3D

    ' Add the PictureBox to the form.
    Me.Controls.Add(Me.PictureBox1)

End Sub


Private Sub ListView1_MouseDown(ByVal sender As Object, _
    ByVal e As MouseEventArgs) Handles ListView1.MouseDown

    Dim selection As ListViewItem = ListView1.GetItemAt(e.X, e.Y)

    ' If the user selects an item in the ListView, display
    ' the image in the PictureBox.
    If (selection IsNot Nothing) Then
        PictureBox1.Image = System.Drawing.Image.FromFile _
            (selection.SubItems(1).Text)
    End If


End Sub

Keterangan

Metode ini GetItemAt memungkinkan Anda menentukan item mana yang terletak di lokasi tertentu dalam wilayah ListView klien kontrol. Anda dapat menggunakan metode ini ketika pengguna mengklik atau mengklik kanan subitem (ketika View properti diatur ke View.Details) dan Anda ingin menentukan item mana yang memiliki subitem yang diklik berdasarkan koordinat mouse pada saat pengguna mengklik mouse.

Catatan

FullRowSelect Ketika nilai properti adalah false, metode ini mengembalikan item hanya ketika lokasi yang ditentukan berada dalam batas item induk (yang ditampilkan di kolom pertama saat kontrol berada dalam mode detail). Anda harus mengatur FullRowSelect properti ke untuk true mengambil item dengan metode ini yang diberikan lokasi dalam batas subitem. Anda juga dapat menggunakan HitTest metode untuk mengambil informasi terperinci tentang item di lokasi tertentu.

Untuk melakukan reposisi item seret dan letakkan dalam ListView, Anda mungkin ingin menggunakan ListViewInsertionMark.NearestIndex metode daripada GetItemAt metode . Metode menemukan ListViewInsertionMark.NearestIndex item terdekat terlepas dari di mana penunjuk mouse berada. Metode ini GetItemAt , di sisi lain, mengembalikan null jika tidak ada item di lokasi yang ditentukan.

Catatan

Kelas ListViewInsertionMark ini hanya didukung pada Windows XP dan Windows Server 2003 saat aplikasi Anda memanggil metode .Application.EnableVisualStyles

Berlaku untuk

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