如何实现ASP.NET 两个下拉框组合实现查询

[guojingmail2009]

两个下拉框对应该两个文本框，如何实现组合查询，请大家帮帮忙！谢谢！
源码：

<asp:TextBox ID="txtTop" runat="server"></asp:TextBox>
<asp:DropDownList ID="ddTop" runat="server">
<asp:ListItem Value="" Text="请选择查询条件"></asp:ListItem>
<asp:ListItem Value="startDate" Text="开始日期查询"></asp:ListItem>
<asp:ListItem Value="customer" Text="客户名称查询"></asp:ListItem>
<asp:ListItem Value="billType" Text="单据类别查询"></asp:ListItem>
<asp:ListItem Value="sales" Text="业务人员查询"></asp:ListItem>
<asp:ListItem Value="billNumber" Text="单号查询"></asp:ListItem>
<asp:ListItem Value="billState" Text="单据结/未结束状态查询"></asp:ListItem>
<asp:ListItem Value="endDate" Text="结束日期查询"></asp:ListItem>
</asp:DropDownList>
</div>
<div>
<asp:TextBox ID="txtBottom" runat="server"></asp:TextBox>
<asp:DropDownList ID="ddBottom" runat="server">
<asp:ListItem Value="" Text="请选择查询条件"></asp:ListItem>
<asp:ListItem Value="startDate" Text="开始日期查询"></asp:ListItem>
<asp:ListItem Value="customer" Text="客户名称查询"></asp:ListItem>
<asp:ListItem Value="billType" Text="单据类别查询"></asp:ListItem>
<asp:ListItem Value="sales" Text="业务人员查询"></asp:ListItem>
<asp:ListItem Value="billNumber" Text="单号查询"></asp:ListItem>
<asp:ListItem Value="billState" Text="单据结/未结束状态查询"></asp:ListItem>
<asp:ListItem Value="endDate" Text="结束日期查询"></asp:ListItem>
<asp:ListItem Value ="cusCancle" Text="客户取消维修查询"></asp:ListItem>
</asp:DropDownList>
</div>
<div>
<asp:Button ID="btnQuery" runat="server" Text="查 询"/>
</div>
<div>
<asp:Repeater ID="rtResult" runat="server">

</asp:Repeater>

[zhongweng]

查询按钮的单击事件中得到两个DropDownList选中的值就行了啊 ddTop.selectValue

[jekyshi]

string sql="select * from tableName where 1=1 "
if(a!="")
{
sql+=" and a='"+a+"'";
}
if(b!="")
{
sql+=" and b='"+b+"'";
}
……
……
……

[mangchao330688]

楼上正解。

[子夜__]

正好昨天给另以为朋友做的DEMO

 DataTable dt = new DataTable();
        protected void Page_Load(object sender, EventArgs e)
        {
            if (!IsPostBack)
            {
                Gvbing();
               
            }
        }

        protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)
        {
            if (this.DropDownList1.SelectedValue != null)
            {
                dt = ReturnDataTable("select * from table where 列='" + this.DropDownList1.SelectedValue + "'");
            }
            else
            {
                dt = ReturnDataTable("select * from table");
            }
            Gvbing();
        }

        protected void DropDownList2_SelectedIndexChanged(object sender, EventArgs e)
        {
            if (this.DropDownList2.SelectedValue != null && this.DropDownList1.SelectedValue != null)
            {
                dt = ReturnDataTable("select * from table where 列='" + this.DropDownList1.SelectedValue + "' and 列='" + this.DropDownList2.SelectedValue + "'");
            }
            else if (this.DropDownList2.SelectedValue == null && this.DropDownList1.SelectedValue != null)
            {
                dt = ReturnDataTable("select * from table where 列='" + this.DropDownList1.SelectedValue + "'");
            }
            else
            {
                dt = ReturnDataTable("select * from table");
            }
            Gvbing();
        }
        public void Gvbing()
        {
            this.GridView1.DataSource = dt;
            this.GridView1.DataBind();
        }

        /// <summary>
        /// 执行有参的查询 返回DataTable
        /// </summary>
        /// <returns>返回DataTable</returns>
        public static DataTable ReturnDataTable(string cmdtext)
        {
            SqlConnection cn = new SqlConnection();
            cn.ConnectionString = "数据库连接字符串";
            DataTable dt = new DataTable();
            SqlCommand cmd = new SqlCommand();
            cmd = new SqlCommand(cmdtext, cn);
            cmd.CommandType = CommandType.Text; ;
            SqlDataReader dr = null;
            using (dr = cmd.ExecuteReader(CommandBehavior.CloseConnection))
            {
                dt.Load(dr);
            }
            return dt;
        }

[wuyq11]

string sql="select * from table where 1=1";
sql+=this.DropDownList1.SelectedValue!=null?" and 列='" + this.DropDownList1.SelectedValue+"'":""
sql+=this.DropDownList1.SelectedValue!=null?" and 列='" + this.DropDownList2.SelectedValue + "'":"";

[skating318]

今天刚注册，没法发帖
刚学asp.net 借楼问个简单问题
DROPDOWNLIST 如何实现 下拉 选择范围 输入关键字 然后搜索？
假设 数据库是A 表是B
刚学，需要详细点的代码：）
感谢先！

[yuanmeixiang]

呵呵！！！ 应该比较简单的