c# - Retain dropdown values in gridview -

i have having grid use checkbox edit grid rows. on checkbox click how can retain dropdown values?

<columns> <asp:templatefield>    <headertemplate>        <asp:checkbox id="chkall" runat="server" autopostback="true"     oncheckedchanged="oncheckedchanged" />    </headertemplate>    <itemtemplate>       <asp:checkbox id="checkbox1" runat="server" autopostback="true" oncheckedchanged="oncheckedchanged" />    </itemtemplate> </asp:templatefield>  <asp:templatefield headertext="scope">    <headerstyle horizontalalign="center" wrap="false" cssclass="header">    </headerstyle>     <itemtemplate>        <asp:label id="lblscope" runat="server" text='<%# bind("scope") %>'></asp:label>        <asp:dropdownlist id="ddlcms" visible="false" runat="server">                 <asp:listitem>yes</asp:listitem>                 <asp:listitem>no</asp:listitem>        </asp:dropdownlist>     </itemtemplate>     <itemstyle wrap="false" cssclass="header" />   </asp:templatefield> </columns> 

i using below code check , uncheck grid rows editing. when click on checkbox not able retail gridview selected dropdown values. ex: third row has column called scope has selected value no. when click on checkbox values yes since order have binded in dropdown.

 protected void oncheckedchanged(object sender, eventargs e)     {         bool isupdatevisible = false;         checkbox chk = (sender checkbox);         if (chk.id == "chkall")         {             foreach (gridviewrow row in updates.rows)             {                 if (row.rowtype == datacontrolrowtype.datarow)                 {                     row.cells[0].controls.oftype<checkbox>().firstordefault().checked = chk.checked;                 }             }         }         checkbox chkall = (updates.headerrow.findcontrol("chkall") checkbox);         chkall.checked = true;         foreach (gridviewrow row in updates.rows)         {             if (row.rowtype == datacontrolrowtype.datarow)             {                 bool ischecked = row.cells[0].controls.oftype<checkbox>().firstordefault().checked;                 (int = 1; < row.cells.count; i++)                 {                     if (row.cells[i].controls.oftype<label>().tolist().count > 0)                     {                         row.cells[i].controls.oftype<label>().firstordefault().visible = !ischecked;                     }                     if (row.cells[i].controls.oftype<textbox>().tolist().count > 0)                     {                         row.cells[i].controls.oftype<textbox>().firstordefault().visible = ischecked;                     }                     if (row.cells[i].controls.oftype<dropdownlist>().tolist().count > 0)                     {                         row.cells[i].controls.oftype<dropdownlist>().firstordefault().visible = ischecked;                     }                     if (ischecked && !isupdatevisible)                     {                         isupdatevisible = true;                     }                     if (!ischecked)                     {                         chkall.checked = false;                     }                 }             }         }         btnsave.visible = isupdatevisible;     } 

first create function this

 private dataset getdata(string query) {     string constring = configurationmanager.connectionstrings["connectionstring"].connectionstring;     sqlcommand cmd = new sqlcommand(query);     using (sqlconnection con = new sqlconnection(constring))     {         using (sqldataadapter da = new sqldataadapter())         {             cmd.connection = con;             da.selectcommand = cmd;             using (dataset ds = new dataset())             {                 da.fill(ds);                 return ds;             }         }     } } 

and on gridview rowdatabound

protected void gridview1_rowdatabound(object sender, gridviewroweventargs e) {     if (e.row.rowtype == datacontrolrowtype.datarow)     {         //find dropdownlist in row         dropdownlist ddlrole = (e.row.findcontrol("ddlrole") dropdownlist);         ddlrole.datasource = getdata("select roletype tablename");         ddlrole.datatextfield = "roletype";         ddlrole.datavaluefield = "roletype";         ddlrole.databind();          //add default item in dropdownlist         ddlrole.items.insert(0, new listitem("please select"));          //select role of user in dropdownlist         string role = (e.row.findcontrol("lblrole") label).text;         ddlrole.items.findbyvalue(role).selected = true;     }        } 

ok may can try viewstate m not sure may these link you

this

here