|
using System;
using System.IO;
using System.Collections.Generic;
using System.Text;
using System.Drawing;
using System.Windows.Forms;
using System.ComponentModel;
using System.Reflection;
namespace ExerciseProgram
{
/// <summary>
/// Create a Custom DataGridViewImageColumn
/// </summary>
public class StringImageColumn : DataGridViewImageColumn
{
public StringImageColumn()
{
this.CellTemplate = new CustomImageCell();
this.ValueType = typeof(string); // value of this column is a string, but it shows images in the cells after formatting
}
}
/// <summary>
/// Create a Custom DataGridViewImageCell
/// </summary>
public class CustomImageCell : DataGridViewImageCell
{
// mapping between filename and image
static System.Collections.Generic.Dictionary<string, Image> dotImages = new Dictionary<string, Image>(); // load up custom dot images
static public System.Collections.Generic.Dictionary<string, Image> Images
{
get
{
return dotImages;
}
}
public CustomImageCell()
{
this.ValueType = typeof(int);
}
protected override object GetFormattedValue(
object value, int rowIndex, ref DataGridViewCellStyle cellStyle,
TypeConverter valueTypeConverter,
TypeConverter formattedValueTypeConverter,
DataGridViewDataErrorContexts context)
{
if (value.GetType() != typeof(string))
return null;
// get the image from the string and return it
LoadImage(value);
// return the mapped image
return dotImages[(string)value];
}
public static void LoadImage(object value)
{
// load the image from the images directory if it does not exist
if (dotImages.ContainsKey((string)value) == false)
{
string path = Path.GetDirectoryName(Application.ExecutablePath) + "\\images\\" + (string)value;
// read the image file
Image theImage = Image.FromFile(path);
// assign the image mapping
dotImages[(string)value] = theImage;
}
}
public override object DefaultNewRowValue
{
get
{
return 0;
}
}
}
} |