[C#] Comparing dates in GridView

Chevy Mark Sunderland

14y6.5k.NET

Hi there, I hope your appreciated help.

First of all I must say that I am a newbie when it comes to net language.

This is my problem.

How to disabled the asp image button "ImageButton4" when today's date is greater than the registration date in my database ?.

For example the record with date registration '2012-04-14' should not display the asp image button "ImageButton4".

If you have link for similar task, please give it me.

Can you help me? thank you in advance.
Your help would be very appreciated

Thanks for your time and hints.

This is my code:

protected void ImageButton1_Click(object sender, EventArgs e)
{
ImageButton myButton = (ImageButton)sender;
string ID = myButton.CommandArgument.ToString();
Response.Redirect("http://localhost/WebApplication1/default.asp?id=" + ID + "&cks=" + Request.Cookies["MyCookie"].Value + "");

}

CommandArgument='<%#Eval("ID")%>' runat="server"
ImageUrl="/Images/updateDB.gif" ToolTip="Update DB"
OnClientClick="return confirm('Confirm?.');"
onclick="ImageButton1_Click" />

6 Replies

Know the answer? Post it — somebody with the same question will find it here.

Chevy Mark Sunderland14y ago
Hello Senthilkumar!
thank you for your help.

I edit my net code with your suggestions but I have the new error.
I hope your help.

Exception Details: System.NullReferenceException: Object reference not set to an instance of an object.

Source Error:

Line 117: if (dtToday > dtDB)
Line 118: {
Line 119: ImageButton4.Enabled = false;
Line 120: }
Line 121: }

DataSourceID="SqlDataSource1"
DataKeyNames="ID"
AllowSorting="True"
AllowPaging="True"
PageSize="15"
AutoGenerateColumns="false"
CssClass="first"
OnRowUpdated="GridView1_RowUpdated"
OnRowDataBound="GridView1_RowDataBound">

CommandArgument='<%#Eval("ID")%>' runat="server"
ImageUrl="/Images/updateDB.gif" ToolTip="Update DB"
OnClientClick="return confirm('Confirm?.');"
onclick="ImageButton1_Click" />

protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
Label Label2 = (Label)e.Row.FindControl("Label2");
ImageButton ImageButton4 = (ImageButton)e.Row.FindControl("ImageButton4");

DateTime dtDB = DateTime.ParseExact(Label2.Text, "dd/MM/yyyy", null);
DateTime dtToday = DateTime.Now;

if (dtToday > dtDB)
{
ImageButton4.Enabled = false;
}
}

}
Senthilkumar14y ago
Hi chevy,

You need to bind the data base date into lblDate control.

And also when you find the control,
Label lblDate = (Label) e.Row.Findcontrol("lblDate");
ImageButton ImageButton4 = (ImageButton) e.Row.FindControl("ImageButton4");
Chevy Mark Sunderland14y ago
Hello Senthilkumar!
thank you for your help.

I try your suggestion but I have this error, why? I hope your help.

Compiler Error Message: CS1061: 'System.Web.UI.WebControls.GridViewRow' does not contain a definition for 'Findcontrol' and no extension method 'Findcontrol' accepting a first argument of type 'System.Web.UI.WebControls.GridViewRow' could be found (are you missing a using directive or an assembly reference?)

<%@ Page Language="C#" Title="Home page" Culture="it-IT" AutoEventWireup="true" %>
<%@ Import Namespace="System.Data" %>
<%@ Import Namespace="System.Data.Odbc" %>
<%@ Import Namespace="System.Configuration" %>
<%@ Import Namespace="System.Collections" %>
<%@ Import Namespace="System.Web" %>
<%@ Import Namespace="System.Web.Services" %>
<%@ Import Namespace="System.Web.Security" %>
<%@ Import Namespace="System.Web.UI" %>
<%@ Import Namespace="System.Web.UI.WebControls" %>
<%@ Import Namespace="System.Web.UI.WebControls.WebParts" %>
<%@ Import Namespace="System.Web.UI.HtmlControls" %>

protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
Label lblDate = e.Row.Findcontrol("lblDate");
ImageButton ImageButton4 = e.Row.FindControl("ImageButton4");
DateTime dtDB = lblDate.Text;
Datetime dtToday = DateTime.Now;

if (dtToday > dtDB)
{
ImageButton4.Enabled = false;
}
}


}

DataSourceID="SqlDataSource1"
DataKeyNames="ID"
AllowSorting="True"
AllowPaging="True"
PageSize="15"
AutoGenerateColumns="false"
CssClass="first"
OnRowUpdated="GridView1_RowUpdated"
OnRowDataBound="GridView1_RowDataBound">

CommandArgument='<%#Eval("ID")%>' runat="server"
ImageUrl="/Images/updateDB.gif" ToolTip="Update DB"
OnClientClick="return confirm('Confirm?.');"
onclick="ImageButton1_Click" />
Senthilkumar14y ago
Hi,

You requirement is very simple,

CommandArgument='<%#Eval("ID")%>' runat="server"
ImageUrl="/Images/updateDB.gif" ToolTip="Update DB"
OnClientClick="return confirm('Confirm?.');"
onclick="ImageButton1_Click" />

what you need to do is, you have store the date from the database into hidden control or invisible label control.
you need to write the Gridview row data bound.

You need to have RowDataBound event,

In the server side,

protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
Label lblDate = e.Row.Findcontrol("lblDate");
ImageButton ImageButton4 = e.Row.FindControl("ImageButton4");
DateTime dtDB = lblDate.Text;
Datetime dtToday = DateTime.Now;
//compare the two dates

if(dtToday > dtDB)
{
ImageButton2.Enabled = false;
}
}
}

Hope this will help you.
Chevy Mark Sunderland14y ago
thanks you, but with your suggestion I have error:
ImageButton4 does not exist in current context

public void Page_Load (Object sender, EventArgs e)
{
OdbcConnection myConnectionString = new OdbcConnection(ConfigurationManager.ConnectionStrings["ConnMySQL"].ConnectionString);
myConnectionString.Open();

myConnectionString.Dispose();
myConnectionString.Close();

lblMessage.Text = "";

DateTime date1 = new DateTime(2009, 8, 1, 0, 0, 0);
DateTime date2 = new DateTime(2009, 8, 1, 12, 0, 0);
int result = DateTime.Compare(date1, date2);

if (result < 0) {
ImageButton4.Enable = false;

}

}

CommandArgument='<%#Eval("ID")%>' runat="server"
ImageUrl="/Images/updateDB.gif" ToolTip="Update DB"
OnClientClick="return confirm('Confirm?.');"
onclick="ImageButton1_Click" />
Abhimanyu K Vatsa14y ago
Use the following concept

protected void Page_Load(object sender, EventArgs e)
{
DateTime date1 = new DateTime(2009, 8, 1, 0, 0, 0);
DateTime date2 = new DateTime(2009, 8, 1, 12, 0, 0);
int result = DateTime.Compare(date1, date2);

if (result < 0)
ImageButton4.Enable = false;
else
//do the rest part
}