Download source - 1 Kb
The .NET platform has simplified a lot of things in Beta1. Simplifications Range from
window controls to Enterprise web services. In this tutorial we will go through some
steps for teaching you how to use the clipboard to transfer data to and from your
.NET applications or any other application.
To transfer clipboard data in .NET we need to use three classes, Clipboard,
DataFormats and IDataObject. These classes reside in the
System.WinForms namespace.
Lets start by creating a simple application to check what type of data the clipboard contains.
Look at the sample below:
Checking Clipboard Data Contents Type
using System;
using System.WinForms;
public class MyClipboardApp
{
public static void Main(string[] args)
{
IDataObject d = Clipboard.GetDataObject();
if(d.GetDataPresent(DataFormats.Bitmap)) {
Console.WriteLine("Bitmap data is Contained in the clipboard.");
} else if(d.GetDataPresent(DataFormats.Text)) {
Console.WriteLine("Text data is Contained in the clipboard.");
} else {
Console.WriteLine("Some other format of data is Contained in the clipboard.");
}
}
}
Lines 1 thru 7 should already be somewhat familiar to you. In Line 8 we assign
an Object called d with an IDataObject interface reference that
encapsulates the clipboard data. We then check the data contained in the clipboard
using the GetDataPresent() method of the IDataObject interface.
The parameter that we pass to GetDataPresent() is the type of data we are
checking for, these values are predefined in the DataFormats Enumeration.
This method returns true if the data encapsulated in this IDataObject instance
can be converted to the specified format else the method returns false.
Once we have the data what can we do with? Well, it is really up to you what you do
with the data. But we will go through another example to show you how to deal with
the data once you have it.
IDataObject has a method GetData(). This method returns an
Object type associated with the format of the data in the clipboard. The following
sample retrieves bitmap data from the clipboard that has been copied from some other
application, like Microsoft paint for instance, and saves the data as a bitmap image.
Retrieving Clipboard Data Contents And Saving
using System;
using System.Drawing;
using System.WinForms;
public class MyClipboardApp
{
public static void Main(string[] args)
{
IDataObject d = Clipboard.GetDataObject();
if(d.GetDataPresent(DataFormats.Bitmap)) {
Bitmap b = (Bitmap)d.GetData(DataFormats.Bitmap);
b.Save(@"c:\mybitmap.bmp");
Console.WriteLine("Bitmap saved to disk!!");
} else {
Console.WriteLine("No bitmap information was contained in the clipboard.");
}
}
}
Before testing this sample, doodle about in paint, select an area then copy it. Then run the program
and look at the output. It is very important to check the data format in the clipboard before you use
it. This is because GetData() returns null if the two formats are incompatible and will
stop normal program execution.
It's also pretty easy to put information into the clipboard programmatically, using only a few lines of code.
Copying Data To Clipboard
IDataObject d = Clipboard.GetDataObject();
d.SetData(DataFormats.Bitmap, new Bitmap(@"c:\myimage.bmp"));
Or adding text is also easy to do.
IDataObject d = Clipboard.GetDataObject();
d.SetData(DataFormats.Text, "Hello World!");
| Hint: For a faster board use IE 4+, choose 'Use DHTML' from the View dropdown and hit 'Set Options'. | |
| |  | | Author | |
| | | Date | |
|
| | -- No entries -- | |
|
|
New thread