using System.Windows.Forms; //required
Clipboard.SetText("your string");
//FOR .NET CORE
Install-Package TextCopy
TextCopy.ClipboardService.SetText("Text to place in clipboard");
Clipboard.SetText("Epic Text");
// Paste text from the clipboard.
private void btnPaste_Click(object sender, EventArgs e)
{
txtPaste.Text = Clipboard.GetText();
}
// Copy text to the clipboard.
private void btnCopy_Click(object sender, EventArgs e)
{
Clipboard.SetText(txtCopy.Text);
}