求最全的JQUERY全选，求高人解决这个，好难啊


 <tr>
                        <td class="style2">
                            适合群体:
                        </td>
                        <td colspan="3" align="left">
                            <asp:CheckBox ID="chkperson" runat="server" Text="全选" onclick="Choseperson(this);" />
                            <div id="FitCrowds" style="display: inline">
                                <asp:CheckBoxList ID="FitCrowd" RepeatDirection="Horizontal" RepeatLayout="Flow"
                                    runat="server" AutoPostBack="true" OnSelectedIndexChanged="FitCrowd_SelectedIndexChanged">
                                </asp:CheckBoxList>
                            </div>
                        </td>
                    </tr>
                    <tr>
                        <td class="style2">
                            适合季节 :
                        </td>
                        <td colspan="3" align="left">
                            <asp:CheckBox Text="全选" ID="chkall" runat="server" onclick="Choseseason(this);" />
                            <div style="display: inline" id="FitSeasons">
                                <asp:CheckBoxList ID="FitSeason" AutoPostBack="true" RepeatDirection="Horizontal"
                                    RepeatLayout="Flow" runat="server" OnSelectedIndexChanged="FitSeason_SelectedIndexChanged">
                                </asp:CheckBoxList>
                            </div>
                        </td>
                    </tr>一个页面中存在两个全选呃，不知道咋搞全选，就四个要求：
1.全选选中，子项选中
2.全选不选择，子项不选中
3.去掉一个子项，全选按钮不选中
4.逐个勾选上子项，全选按钮选中
，求高人