你可以定义一个全局标志来控制颜色的变化。你可以使用LM_SETITEM来设置Syslink，使用LIS_DEFAULTCOLORS来允许Syslink使用自定义颜色。然后你可以在WM_CTLCOLORSTATIC中使用SetTextColor来改变文本的颜色，这些都可以达到你想要的效果。

BOOL m_bSyslinkEnableFlag = TRUE;

case WM_INITDIALOG:
{
    HWND syslinkhwnd = GetDlgItem(hDlg, IDC_SYSLINK2);
    tagLITEM* pItem = new tagLITEM;
    pItem->iLink = 0;
    pItem->mask = LIF_ITEMINDEX | LIF_STATE;
    pItem->state = LIS_ENABLED | LIS_FOCUSED | LIS_DEFAULTCOLORS;
    pItem->stateMask = LIS_ENABLED | LIS_FOCUSED | LIS_DEFAULTCOLORS;
    //LIS_DEFAULTCOLORS can use custom color
    SendMessage(syslinkhwnd, LM_SETITEM, NULL, (LPARAM)pItem);

    return (INT_PTR)TRUE;
}
case WM_CTLCOLORSTATIC:
{
    HWND syslinkhwnd = GetDlgItem(hDlg, IDC_SYSLINK2);
    if (LOWORD(lParam) == LOWORD(syslinkhwnd) && (m_bSyslinkEnableFlag == TRUE))
    {
        //Set the text color blue
        SetTextColor((HDC)wParam, RGB(0, 35, 245));
    }
    else if (LOWORD(lParam) == LOWORD(syslinkhwnd) && (m_bSyslinkEnableFlag == FALSE))
    {
        //Set the text color black when disable
        SetTextColor((HDC)wParam, RGB(0, 0, 0));
    }
    SetBkMode(HDC(wParam), TRANSPARENT);

    //return default background color
    return (INT_PTR)(HBRUSH)CreateSolidBrush(RGB(240, 240, 240));
}

case WM_COMMAND:
if (LOWORD(wParam) == IDC_BUTTON1)
{
    HWND syslinkhwnd = GetDlgItem(hDlg, IDC_SYSLINK2);

    EnableWindow(syslinkhwnd, TRUE);
    //set flag,the clor will change in WM_CTLCOLORSTATIC
    m_bSyslinkEnableFlag = TRUE;
    //redraw control and raise WM_CTLCOLORSTATIC
    RedrawWindow(syslinkhwnd, NULL, NULL, RDW_INVALIDATE);

    return (INT_PTR)TRUE;
}

if (LOWORD(wParam) == IDC_BUTTON2)
{
    HWND syslinkhwnd = GetDlgItem(hDlg, IDC_SYSLINK2);

    EnableWindow(syslinkhwnd, FALSE);
    //set flag,the clor will change in WM_CTLCOLORSTATIC
    m_bSyslinkEnableFlag = FALSE;
    //redraw control and raise WM_CTLCOLORSTATIC
    RedrawWindow(syslinkhwnd, NULL, NULL, RDW_INVALIDATE);

    return (INT_PTR)TRUE;
}