在下拉列表中显示文本框值

我有一个gridview，在gridview标题中我有两个控件文本框和下拉列表。

i想要在textbox中键入一些值，如果value在dropdown中则显示该值，否则为no。我试过，但我没有得到gridview控件id。但我尝试了一个演示，当我在gridview文本中键入然后该值显示在gridview外的下拉列表。但我不知道为什么它没有发生与gridview下拉菜单。



我的尝试：

I have one gridview,in gridview header I have two controls textbox and dropdown.
i want that I want to type some value in textbox if value is in dropdown then its show that value otherwise no.i have tried but i am not getting gridview control id.but i hv tried one demo that while i am typing in gridview text then that value is showing in dropdown which is outside of gridview.but i don't know why its not happening with gridview dropdown.

What I have tried:

<Columns>
                <asp:TemplateField HeaderText="code" SortExpression="code" >
                    <ItemTemplate>
                        <asp:Label ID="Labelid" runat="server" Text='<%# Eval("code") %>'></asp:Label>
                    </ItemTemplate>
                </asp:TemplateField>

                <asp:TemplateField HeaderText="Name" SortExpression="name">
                 <HeaderTemplate>
<table>
<tr>
<td>
UserName
<asp:Button ID="Buttonname" runat="server" Text="▼" Height="15px" OnClick="Buttonnameclick"/>
</td>
</tr>
<tr>
      <asp:DropDownList ID="DropDownListname" runat="server">
    <asp:ListItem>Pragya</asp:ListItem>
     <asp:ListItem>a</asp:ListItem>
            <asp:ListItem>Priyanka</asp:ListItem>
            <asp:ListItem>hema</asp:ListItem>
            <asp:ListItem>Shiv</asp:ListItem>
    </asp:DropDownList>
    <asp:TextBox ID="TextBoxname" runat="server" OnTextChanged="nametextfilter" AutoPostBack="true" AutoCompleteType="Search" onkeyup="sync(this)" ></asp:TextBox>
</div>
</td>
</tr>
</table>
</HeaderTemplate>  

我的查询



函数同步（文本框）{

document.getElementById（'<％= DropDownList1.ClientID ％GT; '）。value = textbox.value;

var GridView = document.getElementById（'<％= GridView1emp

for（var i = 0;我< 1; i ++）{

var txtAmountReceive = $（input [id * = DropDownListname]）;

txtAmountReceive.value = textbox.value;

}

My query

function sync(textbox) {
document.getElementById('<%=DropDownList1.ClientID %>').value = textbox.value;
var GridView = document.getElementById('<%=GridView1emp
for ( var i = 0; i < 1; i++) {
var txtAmountReceive = $("input[id*=DropDownListname]");
txtAmountReceive.value = textbox.value;
}