[الطالب]

سلام

كود :

Sub RichTextBoxHighlightText(ByVal richTextBox As RichTextBox, ByVal [string] As String, ByVal color As Color)
    Dim c As Color = richTextBox.ForeColor
    richTextBox.SelectAll()
    richTextBox.SelectionColor = c
    For i = 0 To richTextBox.TextLength
        richTextBox.Find([string], i, RichTextBoxFinds.None)
        richTextBox.SelectionColor = color
    Next
    richTextBox.ForeColor = c
End Sub

موفقين