Member Avatar for thuyson 
private void btThem_Click(object sender, EventArgs e)
        {
            for(int i=0;i<dataGridView1.Rows.Count-1;i++)
            {
                
                if(dataGridView1.Rows[i].Cells["Checked"].Value ==true)
                {
                   
                    cmTheoHocLop.Parameters["@X"].Value = tbMSSV.Text;
                    cmTheoHocLop.Parameters["@Y"].Value = dataGridView1.Rows[i].Cells["MaLop"].Value;
                    sqlConnection1.Open();
                    cmTheoHocLop.ExecuteNonQuery();
                    sqlConnection1.Close();
                }
            
            }
           
        }

it has a error :Error 3 Operator '==' cannot be applied to operands of type 'object' and 'bool' D:\lvthao\QLHP\QLHP\FrmDKHP.cs 48 20 QLHP

Thanks so much!!

  • 5 Contributors
  • 16 Replies
  • 271 Views
  • 1 Week Discussion Span
  • Latest Post Latest Post by andrewll2
Member Avatar for apegram

Try casting the left side.

if((bool)dataGridView1.Rows[i].Cells["Checked"].Value ==true)
Member Avatar for thuyson

i did it,but it has error: Specified cast is not valid.
Please help me!
Thank you!!

Member Avatar for jinus

#
if(dataGridView1.Rows.Cells["Checked"].Value ==true)
It is incorect as cells cant be checked

CheckBox cb;
cb = (CheckBox) e.Item.FindControl("CheckBox2");

then check for checkbox if its ok

Member Avatar for thuyson

it's image error

Error.zip (91.69 KB)
Member Avatar for jinus

send me whole code then

Member Avatar for thuyson 
private void btThem_Click(object sender, EventArgs e)
        {
            
                for (int i = 0; i < dataGridView1.Rows.Count - 1; i++)
                {
                   
                 
                    if ((bool)dataGridView1.Rows[i].Cells["Chon"].Value == true)
                    {

                        cmTheoHocLop.Parameters["@X"].Value = tbMSSV.Text;
                        cmTheoHocLop.Parameters["@Y"].Value = dataGridView1.Rows[i].Cells["MaLop"].Value;
                        sqlConnection1.Open();
                        cmTheoHocLop.ExecuteNonQuery();
                        sqlConnection1.Close();
                    }

                }
           
        }

it has a error :Object reference not set to an instance of an object.

Member Avatar for jinus

aspx page and code i want to see where is your check box
right now u r taking cell value and not checkbox value

Member Avatar for thuyson

i don't understand !

Member Avatar for jinus

you just send code what you wrote on btThem_Click
can you send me aspx page also so that i can see where is your datagrid and checkbox

sample of my page

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="AttendanceInputScreen.aspx.cs"
    Inherits="AttendanceMobilePortal.AttendanceInputScreen" %>

<%@ Register Assembly="C1.Web.iPhone.3" Namespace="C1.Web.iPhone.C1Button" TagPrefix="C1Button" %>
<%@ Register Assembly="C1.Web.iPhone.3" Namespace="C1.Web.iPhone.C1PickerView" TagPrefix="C1PickerView" %>
<%@ Register Assembly="C1.Web.iPhone.3" Namespace="C1.Web.iPhone.C1ViewPort" TagPrefix="cc1" %>
<%@ Register Assembly="C1.Web.iPhone.3" Namespace="C1.Web.iPhone.C1NavigationList"
    TagPrefix="C1NavigationList" %>
<%@ Register Assembly="C1.Web.iPhone.3" Namespace="C1.Web.iPhone.C1SegmentedButtons"
    TagPrefix="C1SegmentedButtons" %>
<%@ Register Assembly="C1.Web.iPhone.3" Namespace="C1.Web.iPhone.C1Calendar" TagPrefix="C1Calendar" %>
<%@ Register Assembly="C1.Web.iPhone.3" Namespace="C1.Web.iPhone.C1Dialog" TagPrefix="C1Dialog" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head id="Head1" runat="server">
    <title>Attendance Input Screen</title>
    <meta name="apple-mobile-web-app-capable" content="yes" />
    <link rel="Stylesheet" href="StyleSheet.css" type="text/css" media="all" />
    <style type="text/css" media="all">
        .C1CustomItemSample
        {
            width: 100%;
            height: 30px;
            display: block;
            position: relative;
        }
        .C1CustomItemSample input
        {
            position: absolute;
            top: 2px;
            left: 145px;
            width: 90px;
            height: 30px;
            -webkit-border-radius: 5px;
            font-family: Arial;
            font-size: 14px; /*border: none;*/
            margin-top: 2px;
        }
        .C1CustomItemSample img
        {
            position: absolute;
            top: 5px;
            left: 260px;
            -webkit-border-radius: 5px;
            font-family: Arial;
            font-size: 16px;
        }
        .session
        {
            position: absolute;
            top: 2px;
            left: 140px;
            width: 125px;
            height: 30px;
            -webkit-border-radius: 5px;
            font-family: Arial;
            font-size: 16px;
            text-align: center;
            color: white;
        }
        .C1Landscape .C1CustomItemSample input
        {
            width: 300px;
        }
        .C1CustomItemSample .C1SampleLabel
        {
            position: absolute;
            margin-left: 10px;
            display: block;
            top: 12px;
            left: 5px;
            font-family: Helvetica;
            font-size: 14px;
            font-weight: bold;
            color: #000000;
            text-shadow: #FFFFFF 0px 1px 1px;
        }
        .C1CustomItemSample .C1SampleRightLabel
        {
            position: absolute;
            display: block;
            top: 12px;
            right: 5px;
            font-weight: bold;
            float: right;
            font-family: Helvetica;
            font-size: 16px;
            font-weight: bold;
            color: #324F85;
            text-shadow: #FFFFFF 0px 1px 1px;
        }
        .C1SampleCustomTextStyle span, .C1SampleCustomTextStyle div
        {
            font-size: 17px;
            font-weight: bold;
            color: #FFFFFF;
            text-shadow: #000000 1px 1px 2px;
        }
        .C1SampleWrongInputItem *
        {
            color: Red;
        }
        .C1SampleApprovedItem *
        {
            color: Green;
        }
        .C1SegmentedButton
        {
            margin-top: 2px !important;
            width: 10px !important;
            padding: 0 !important;
            text-align: center !important;
        }
        .C1Selected .C1TextNode
        {
            color: #FFFFFF !important;
            font-style: normal !important;
        }
        .C1First .C1TextNode
        {
            padding-left: 10px !important;
            font-style: normal !important;
        }
        .C1Last .C1TextNode
        {
            padding-left: 14px !important;
            font-style: normal !important;
        }
        .C1SegmentedButtons_IPhone
        {
            left: 135px !important;
        }
    </style>
</head>
<body onload="fillcurrentdate();">
    <form id="form1" runat="server">
    <asp:ScriptManager ID="ScriptManager1" runat="server" />

    <script language="javascript" type="text/javascript">

    function fillcurrentdate() {
            var date = new Date();
            var dayNumber = date.getDate();
            var monthNumber = date.getMonth() + 1;

            if (dayNumber < 10)
            {
                dayNumber = "0" + dayNumber;
            }
            if (monthNumber < 10)
            {
                monthNumber = "0" + monthNumber;
            }

            document.getElementById("txtRoasterDate").value = monthNumber + "/" + dayNumber + "/" + date.getFullYear();
        }

    function showCalendar() {
            Sys.Application.findComponent("<%=C1Dialog1.ClientID%>").show();
        }

        function onCalendarSelectionChanged(calendar, selectionEventArgs){
            var selectedDates = selectionEventArgs.get_selectedDates();

            document.getElementById("txtRoasterDate").value = (selectedDates[0].getMonth()+1) + "/" + selectedDates[0].getDate() + "/" + selectedDates[0].getFullYear();

            /*var navList = Sys.Application.findComponent("<%=C1NavigationList1.ClientID%>");  
            var newItem = new C1.Web.iPhone.C1NavigationList.C1NavigationListItem();
            navList.get_items().add(newItem);
            newItem.set_text(selectedDates[0]);
            newItem.set_topText("" + selectedDates[0].getFullYear() + " / " + (selectedDates[0].getMonth()+1) + " / " + selectedDates[0].getDay());
            newItem.set_bottomText("Just added");
            newItem.set_commandName("JustAddedDate");            
            */

            Sys.Application.findComponent("<%=C1Dialog1.ClientID%>").hide();

            //document.location.href = "AttendanceInputScreen.aspx?status=take&dt=" + (selectedDates[0].getMonth()+1) + "/" + selectedDates[0].getDate() + "/" + selectedDates[0].getFullYear();
        }
        /*function OnClientItemClick_C1NavigationList1(item) {
            if(item.get_commandName() == "JustAddedDate") {
                $().c1iPhone().c1confirm(function(){item.remove();}, "Remove " + item.get_text() + "?", {ok:"Remove", cancel:"No, cancel"});
            }
        }*/

    function showRosterIDPicker() {
            Sys.Application.findComponent("<%=C1Dialog2.ClientID%>").show();
        }

    function doDialogChoose()
     {  
            // get dialog results and close dialog:
            var oPickerView = Sys.Application.findComponent("<%=C1PickerView_RosterIDs.ClientID%>");    

            //alert(document.getElementById("C1Dialog2_CntPnl_ctl00").value);

            var selectedValue = oPickerView.getSelectedItemValue("rosterids");            
            document.getElementById("txtRoasterID").value = selectedValue

            //_activeItem.set_topText(selectedValue);

            Sys.Application.findComponent("<%=C1Dialog2.ClientID%>").hide();
     }
     function doDialogCancel()
     {
        // close dialog:
         Sys.Application.findComponent("<%=C1Dialog2.ClientID%>").hide(); 
     }

    function validateAndSubmitForm() {
        var dbn = document.getElementById("txtSchoolDBN").value;
        var roasterDate = document.getElementById("txtRoasterDate").value;
        var roasterID = document.getElementById("txtRoasterID").value;
        if(dbn == "")
        {
            alert("School DBN cannot be empty.");
            return false;
        } 
        else if(roasterDate == "") 
        {
            alert("Roaster Date cannot be empty.");
            return false;
        }
        else if(roasterID == "") 
        {
            alert("Roaster ID cannot be empty.");
            return false;
        }
        else
        {
            return true;
        }

        /*__doPostBack();*/
    }
    </script>

    <div class="C1SampleContainer">
        <cc1:C1ViewPort ID="C1ViewPort1" runat="server" Text="Attendance" UrlBarVisible="false"
            ToolBarVisible="true" CssClass="C1SampleContainer">
            <ToolBar>
                <table width="100%">
                    <tr>
                        <td align="right">
                            <img src="images/nyc_logo.gif" height="35px" alt="" />
                        </td>
                    </tr>
                </table>
            </ToolBar>
            <LeftButton ButtonType="Back" Text="Home" NavigateUrl="Default.aspx" />
            <RightButton ID="RightButton1" Text="Log Out" OnClick="OnLogOutClick" runat="server"
                AutoPostBack="true" />
            <Content>
                <C1NavigationList:C1NavigationList ID="C1NavigationList1" runat="server" NavigationListType="RoundedCornersList"
                    LoadOnDemand="false" TrackItemsStructure="true">
                    <Items>
                        <C1NavigationList:C1NavigationListGroupItem ID="C1NavigationListGroupItem1" runat="server">
                            <Items>
                                <C1NavigationList:C1NavigationListItem ID="C1NavigationListItem1" runat="server">
                                    <Template>
                                        <div class="C1CustomItemSample">
                                            <span class="C1SampleLabel">School DBN</span>
                                            <input type="text" id="txtSchoolDBN" name="txtSchoolDBN" size="12" value="11X545" />
                                        </div>
                                    </Template>
                                </C1NavigationList:C1NavigationListItem>
                                <C1NavigationList:C1NavigationListItem ID="C1NavigationListItem2" runat="server">
                                    <Template>
                                        <div class="C1CustomItemSample">
                                            <span class="C1SampleLabel">Roster Date</span>
                                            <input type="text" id="txtRoasterDate" name="txtRoasterDate" size="12" readonly="readonly"
                                                onclick="javascript:showCalendar();" />
                                            &nbsp;&nbsp;
                                            <img src="images/calendar.png" title="click here to select date" onclick="javascript:showCalendar();"
                                                alt="" />
                                        </div>
                                    </Template>
                                </C1NavigationList:C1NavigationListItem>
                                <C1NavigationList:C1NavigationListItem ID="C1NavigationListItem3" runat="server">
                                    <Template>
                                        <div class="C1CustomItemSample">
                                            <span class="C1SampleLabel">Roaster Identifier</span>
                                            <input type="text" id="txtRoasterID" name="txtRoasterID" size="12" value="H8R-01"
                                                onclick="javascript:showRosterIDPicker();" />
                                        </div>
                                    </Template>
                                </C1NavigationList:C1NavigationListItem>
                                <C1NavigationList:C1NavigationListItem ID="C1NavigationListItem4" runat="server">
                                    <Template>
                                        <div class="C1CustomItemSample">
                                            <span class="C1SampleLabel">Session</span>
                                            <C1SegmentedButtons:C1SegmentedButtons CssClass="session" ID="C1SegmentedButtons1"
                                                runat="server">
                                                <Buttons>
                                                    <C1SegmentedButtons:C1SegmentedButton Text="AM" Height="38px" Width="40px" />
                                                    <C1SegmentedButtons:C1SegmentedButton Text="PM" Height="38px" Width="40px" />
                                                </Buttons>
                                            </C1SegmentedButtons:C1SegmentedButtons>
                                        </div>
                                    </Template>
                                </C1NavigationList:C1NavigationListItem>
                            </Items>
                        </C1NavigationList:C1NavigationListGroupItem>
                    </Items>
                </C1NavigationList:C1NavigationList>
            </Content>
            <RightButton ID="RightButton"></RightButton>
        </cc1:C1ViewPort>
    </div>
    <C1Dialog:C1Dialog runat="server" ID="C1Dialog1" DisplayVisible="false">
        <Content>
            <br />
            <div id="DialogTitle1" style="width: 100%; text-align: center; font-family: Helvetica;
                color: #FFFFFF; font-size: 16px; font-weight: bold;">
                Choose date.
            </div>
            <br />
            <C1Calendar:C1Calendar runat="server" ID="C1Calendar1" 
                OnClientSelectedDatesChanged="onCalendarSelectionChanged">
            </C1Calendar:C1Calendar>
            <br />
        </Content>
    </C1Dialog:C1Dialog>
    <C1Dialog:C1Dialog runat="server" ID="C1Dialog2" DisplayVisible="false">
        <Content>
            <br />
            <div id="Div1" style="width: 100%; text-align: center; font-family: Helvetica; color: #FFFFFF;
                font-size: 16px; font-weight: bold;">
                Choose Roster ID.
            </div>
            <br />
            <C1PickerView:C1PickerView runat="server" ID="C1PickerView_RosterIDs" DisplayVisible="true">
                <Pickers>
                    <C1PickerView:C1Picker Name="rosterids" Width="150px"></C1PickerView:C1Picker>
                </Pickers>
            </C1PickerView:C1PickerView>
            <br />
            <div style="width: 90%; margin-left: 5%; margin-right: 5%">
                <c1button:c1button id="C1Button1" runat="server" text="Choose" buttontype="Primary"
                    width="97%" onclientclick="doDialogChoose" />
                <br />
                <br />
                <c1button:c1button id="C1Button2" runat="server" text="Cancel" buttontype="Destructive"
                    width="97%" onclientclick="doDialogCancel" />
            </div>
            <br />
        </Content>
    </C1Dialog:C1Dialog>
    </form>
</body>
</html>
Edited by mike_2000_17 because: Fixed formatting
Member Avatar for thuyson 
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;

namespace QLHP
{
    public partial class FrmDKHP : Form
    {
        public FrmDKHP()
        {
            InitializeComponent();
        }

        private void FrmDKHP_Load(object sender, EventArgs e)
        {
            daNganhHoc.Fill(myDS1.NganhHoc);
        }
        private void btHienThi_Click(object sender, EventArgs e)
        {

            daLopHoc.SelectCommand.Parameters["@A"].Value = cbTenNganh.SelectedValue;
            daLopHoc.SelectCommand.Parameters["@B"].Value = cbHocKy.SelectedItem;
            //daLopHoc.SelectCommand.Parameters["@D"].Value = tbNam.Text;
            daLopHoc.Fill(myDS1.LopHoc);
            /*for (int i = 0; i < dataGridView1.Rows.Count - 1; i++)
            {
                dataGridView1.Rows[i].Cells["Chon"].Value = true;
            }*/
        }

        private void btThoat_Click(object sender, EventArgs e)
        {
            this.Hide();
            FrmPDT f2 = new FrmPDT();
            f2.ShowDialog();
            this.Close();
        }

        private void btThem_Click(object sender, EventArgs e)
        {
            
                for (int i = 0; i < dataGridView1.Rows.Count - 1; i++)
                {
                   
                 
                    if ((bool)(dataGridView1.Rows[i].Cells["Chon"]).Value == true)
                    {

                        cmTheoHocLop.Parameters["@X"].Value = tbMSSV.Text;
                        cmTheoHocLop.Parameters["@Y"].Value = dataGridView1.Rows[i].Cells["MaLop"].Value;
                        sqlConnection1.Open();
                        cmTheoHocLop.ExecuteNonQuery();
                        sqlConnection1.Close();
                      
                    }

                }
           
        }

        private void btClear_Click(object sender, EventArgs e)
        {
            myDS1.TheoHocLop.Clear();
        }

       

        
    }
}
Member Avatar for thuyson

Please help me!
Thanks!

Member Avatar for thuyson 
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;

namespace QLHP
{
    public partial class FrmDKHP : Form
    {
        public FrmDKHP()
        {
            InitializeComponent();
        }

        private void FrmDKHP_Load(object sender, EventArgs e)
        {
            daNganhHoc.Fill(myDS1.NganhHoc);
        }
        private void btHienThi_Click(object sender, EventArgs e)
        {

            daLopHoc.SelectCommand.Parameters["@A"].Value = cbTenNganh.SelectedValue;
            daLopHoc.SelectCommand.Parameters["@B"].Value = cbHocKy.SelectedItem;
            //daLopHoc.SelectCommand.Parameters["@D"].Value = tbNam.Text;
            daLopHoc.Fill(myDS1.LopHoc);
            /*for (int i = 0; i < dataGridView1.Rows.Count - 1; i++)
            {
                dataGridView1.Rows[i].Cells["Chon"].Value = true;
            }*/
        }

        private void btThoat_Click(object sender, EventArgs e)
        {
            this.Hide();
            FrmPDT f2 = new FrmPDT();
            f2.ShowDialog();
            this.Close();
        }

        private void btThem_Click(object sender, EventArgs e)
        {
            
                for (int i = 0; i < dataGridView1.Rows.Count - 1; i++)
                {
                   
                 
                    if ((bool)(dataGridView1.Rows[i].Cells["Chon"]).Value == true)
                    {

                        cmTheoHocLop.Parameters["@X"].Value = tbMSSV.Text;
                        cmTheoHocLop.Parameters["@Y"].Value = dataGridView1.Rows[i].Cells["MaLop"].Value;
                        sqlConnection1.Open();
                        cmTheoHocLop.ExecuteNonQuery();
                        sqlConnection1.Close();
                      
                    }

                }
           
        }

        private void btClear_Click(object sender, EventArgs e)
        {
            myDS1.TheoHocLop.Clear();
        }

       

        
    }
}

Please help me!
Thanks!

Member Avatar for nick.crane

You have the parentheses arount the wrong part in the casting.

if ((bool)(dataGridView1.Rows.Cells["Chon"]).Value == true)

Try this

if ((bool)(dataGridView1.Rows.Cells["Chon"].Value) == true)

Member Avatar for thuyson

I try it,it has the same error.But i did it successful!

if(dataGridView1.Rows[i].Cells["Chon"].Selected==true)
Member Avatar for thuyson

Thanks for ur post!

Be a part of the DaniWeb community

We're a friendly, industry-focused community of developers, IT pros, digital marketers, and technology enthusiasts meeting, networking, learning, and sharing knowledge.