在asp:TextBox 中加了ReadOnly="true" 后就不能实现回传了 解决方法

1. 页面

Code
<asp:RadioButtonList ID="RadioButtonList2" runat="server" AutoPostBack="true"  OnSelectedIndexChanged="RadioButtonList2_SelectedIndexChanged"
                                                            RepeatDirection="Horizontal" RepeatLayout="Flow" Width="113px">
                                                            <asp:ListItem Selected="True">精确</asp:ListItem>
                                                            <asp:ListItem>模糊</asp:ListItem>
                                                        </asp:RadioButtonList>

<asp:TextBox ID="txtPreDeptName" runat="server" CssClass="inp-login" onmouseover="this.style.borderColor='#9ecc00'"
                                                            onmouseout="this.style.borderColor='#ccc'"  Width="207px" />

2. C#代码

Code
protected void RadioButtonList2_SelectedIndexChanged(object sender, EventArgs e)
    {
        if (RadioButtonList2.SelectedValue.Equals("模糊"))
        {
            //删除一个属性
            txtPreDeptName.Attributes.Remove("Readonly");
        }
        else
        {
            /*
             <asp:TextBox ID="txtPreDeptName" runat="server" ReadOnly="true" />
             注意 不能在这里加 ReadOnly="true" 加了后就不能实现回传了.
             * 必须用 txtPreDeptName.Attributes.Add("Readonly", "True"); 
             */
            txtPreDeptName.Attributes.Add("Readonly", "True"); 
        }
    }