选中的单选按钮未正确触发

我有一个收音机按钮

 <asp:RadioButton ID="AMRadioButton" runat="server" AutoPostBack="True" GroupName="TypeGroup"
                                OnCheckedChanged="AMRadioButton_CheckedChanged" Text="Accounting Date" />
                            <asp:RadioButton ID="LMRadioButton" runat="server" AutoPostBack="True" GroupName="TypeGroup"
                                OnCheckedChanged="LMRadioButton_CheckedChanged" Text="Loan Date" />

我有一个密码

 protected void AddButton_Click(object sender, EventArgs e)
    {
        if (AMRadioButton.Checked = true)
        {
            prenda.Bcode = BranchCodetxtbox.Text;
            prenda.AccountingMonth = YearDropDownList.SelectedValue + "/" + MonthDropDownList.SelectedValue;
            prenda.Jprincipal = Convert.ToDecimal(JewelryTextBox.Text);
            prenda.Aprincipal =  Convert.ToDecimal(ApplianceTextBox.Text);
            prenda.Cprincipal =  Convert.ToDecimal(CellphoneTextBox.Text);
            user.UserID = Session["UserID"].ToString();
            servs.UploadPrendaAM(prenda, user);
            Session["Count"] = "1";
            Response.Write("<script language='javascript'>window.alert('Success!');window.location='DataEntryPage.aspx';</script>");

        }
        else if (LMRadioButton.Checked = true)
        {
            prenda.Bcode = BranchCodetxtbox.Text;
            prenda.LoanMonth = YearDropDownList.SelectedValue + "/" + MonthDropDownList.SelectedValue;
            prenda.Jprincipal =  Convert.ToDecimal(JewelryTextBox.Text);
            prenda.Aprincipal =  Convert.ToDecimal(ApplianceTextBox.Text);
            prenda.Cprincipal =  Convert.ToDecimal(CellphoneTextBox.Text);
            user.UserID = Session["UserID"].ToString();
            servs.UploadPrendaLM(prenda, user);
            Session["Count"] = "1";
            Response.Write("<script language='javascript'>window.alert('Success!');window.location='DataEntryPage.aspx';</script>");

        }
    }

问题是,即使我已经检查/选择了LMradio按钮,代码仍然会进入 if(AMRadioButton.Checked = true) 这不是我想要的,当然,当我勾选LMradio按钮时,代码应该是 else if (LMRadioButton.Checked = true) 在这里不在amradiobutton。检查。

我错过什么了吗?请帮忙