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Large Dataset

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ListView size limit? Thank you all for your concern and assistance. I've figured out how to list the Items themselves (without having to use a DataTable) The next step for me is to use the ListViewItem.SelectedIndices to deal with a specific object in the Typed List of objects. the combination that worked for showing the items goes something like this: this code is from a test that I did at home: ListViewItem[] items = new ListViewItem[500000]; List<Class1> objects=new List<Class1>(); Class1 obj; private int seed = 0; private void button1_Click(object sender, EventArgs e) { lvTest.VirtualListSize = items.Length; for(int i=0;i<items.Length;i++){ obj = new Class1(); obj.ID = i; obj.Name = "Object_" + i; objects.Add(obj); private void lvTest_RetrieveVirtualItem(object sender, RetrieveVirtualItemEventArgs e) { if (items[e.ItemIndex] == null) { e.Item = new ListViewItem(objects[e.ItemIndex].ID.ToString()); e.Item.SubItems.Add(objects[e.ItemIndex].Name); } else { e.Item = items[e.ItemIndex]; items[ i] = lvTest.Items[ i];

.net - Prevent double entries in ListView using C# C# - Dealing with very large datasets & just in time loading. Paging Data with DataGridView in VirtualMode. Download source files - 23.2 KB Introduction This article illustrates an example of paged data retrieval and displaying a large amount of data on the DataGridView control in VirtualMode. Background Displaying millions of rows of data on a Form consumes lots of memory and can easily make the UI unresponsive.

In order for the UI to display large amounts of data and remain responsive, the UI should only load and display data that it needs to show. There are other things that must be considered to improve the performance of the DataGridView control. For this article, I will present an example of a Form with only one DataGridView loaded with over a million rows of names.

Using the Code There are two parts in the example: The use of DataGridView VirtualMode, and Paged data retrieval How to Use DataGridView VirtualMode There are three main things that must be done to use DataGridView in VirtualMode: In Form1's constructor, RowCount is set to the total number of rows. Paged Data Retrieval History. DataGridView with LARGE dataset. The code below is a full application demonstrating the problem. It consumes 150Meg of RAM on my system. using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Windows.Forms; public Form1() { InitializeComponent(); } private void Form1_Load(object sender, EventArgs e) { dataGridView1.RowCount = 10000000; } } partial class Form1 { /// <summary> /// Required designer variable. /// </summary> private System.ComponentModel.IContainer components = null; /// <summary> /// Clean up any resources being used. /// </summary> /// <param name="disposing">true if managed resources should be disposed; otherwise, false.

#region Windows Form Designer generated code ((System.ComponentModel.ISupportInitialize)(this.dataGridView1)).EndInit(); this.ResumeLayout(false); #endregion.