"Red"、"Yellow"、"ActiveCaption"、"ButtonFace" といった『色名』を Color 化できます。
Private Sub TextBox1_TextChanged(sender As Object, e As EventArgs) Handles TextBox1.TextChanged Dim s As String = TextBox1.Text Try Dim C As Color = Color.FromName(s) PictureBox1.BackColor = C Catch ex As Exception PictureBox1.ResetBackColor() End Try End Sub
Try Dim cnv As New ColorConverter() Dim C As Color = DirectCast(cnv.ConvertFromString(s), Color) PictureBox1.BackColor = C Catch ex As Exception PictureBox1.ResetBackColor() End Try