Disable Button on CheckBox unchecked

[Ebenezer]

I am using the code below to force customers to select item from a Grid CheckBox

function GetCheckedItemCountbtnClick() {

            var checkedcount = 0;

            var grid = $find("<%=gvSummary.ClientID %>");           

            for (var i = 0; i < grid.get_masterTableView().get_dataItems().length; i++) {

                var objchkbox = grid.get_masterTableView().get_dataItems()[i].findElement("CheckBoxStatus");

                 if (objchkbox.checked) {

                    checkedcount++;

                }

                 

                //}

                if (checkedcount > 8) {

                     objchkbox.checked = false;

                  

                    alert("Please select only 8 item");

                    return false;                  

 

                }

            }

            if (checkedcount == 0) {

                  

                alert("Please Check at least one CheckBox");

                 

                return false;

 

            }

 

         

        }


I have a Button I want to disable when the 'checkedcount ==0' unless an item is checked

<asp:Button ID="btnPrint" runat="server" Font-Size="X-Small" OnClick="btnPrint_Click"

                            Text="Print" ToolTip="Create a  report..." />

Nothing seems to work for me. Any idea will be appreciated.

[Shinu]

Hi Ebenezer,

I guess you are trying to disable the Button 'btnPrint' on another Button Click. Please have a look into the following code snippet that I tried.

ASPX:

<telerik:RadButton ID="RadButton1" runat="server" Text="CheckedItems" OnClientClicked="GetCheckedItemCountbtnClick"
    AutoPostBack="false">
</telerik:RadButton>
<br />
<asp:Button ID="btnPrint" runat="server" Font-Size="X-Small" Text="Print" ToolTip="Create a  report..." />

JavaScript:

<script type="text/javascript">
    function GetCheckedItemCountbtnClick(sender, args) {
        var checkedcount = 0;
        var grid = $find("<%=gvSummary.ClientID %>");
        for (var i = 0; i < grid.get_masterTableView().get_dataItems().length; i++) {
            var objchkbox = grid.get_masterTableView().get_dataItems()[i].findElement("CheckBoxStatus");
            if (objchkbox.checked) {
                checkedcount++;
            }
            if (checkedcount > 8) {
                objchkbox.checked = false;
                alert("Please select only 8 item");
                return false;
            }
        }
        if (checkedcount == 0) {
            alert("Please Check at least one CheckBox");
            var button = document.getElementById("btnPrint");//accessing the asp button
            button.disabled = true;//disabling the button
            return false;
        }
    }
</script>

Thanks,
Shinu.

[Ebenezer]

Hi Shinu
Thanks for your response but I am getting an error
Error: Unable to set value of the property 'disabled': object is null or undefined

[Ebenezer]

Solved. I had to change
if (checkedcount == 0) {
                alert("Please Check at least one CheckBox");
                var button = document.getElementById("<%=btnPrint.ClientID %>"); //accessing the asp button       
                button.disabled = true; //disabling the button
                return false;
            }