I think that only the option uses the Insert option.
Try this code
private void richTextBox1_KeyDown(object sender, KeyEventArgs e) { if (richTextBox1.Text.Contains(":-)")) { richTextBox1.SelectionStart = richTextBox1.Find(":-)", RichTextBoxFinds.WholeWord); richTextBox1.SelectionLength = 3; Clipboard.SetImage(im.Images["smile.png"]); this.richTextBox1.Paste(); } }
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