ASP.NET

Re: Avoiding Page Refresh on F5

21-Apr-08 9:20

I am handing a GridView fully in client-side(am using callbacks to avoid page refresh). that is, i am having a certain No. of records in a GridView each bound with a check box, and while checking each of the checkboxes, i am doing some operation internally.

When press F5 or refresh the page, the selected records are cleared.

(To avoid this problem, i used ViewState to maintain the each record's status. But was helpless. But Session did well.)

The concern is, i shouldn't use any Session Variables, and even after F5 the records must be without modifications.

Or else, is it possible to avoid such page refreshing?

Thanks in advance.

Muthu.G

Sandeep Akhare21-Apr-08 19:16

Sandeep Akhare

21-Apr-08 19:16

I think we should not capture any browser events except for the worst case.
Your application is behaving as it should,User clicks refresh button/F5 to get last/latest/reset content.
I don't understand why you want to restrict user not to click F5. If any data is getting lost then it totally beacuse of user unknowingness.
Any way take a look at this article, Not so easy to avoid page refresh
http://msdn2.microsoft.com/en-us/library/ms379557(VS.80).aspx#bedrockas_topic2[^]

Thanks and Regards
Sandeep

If If you look at what you do not have in life, you don't have anything,
If you look at what you have in life, you have everything... "

Re: Avoiding Page Refresh on F5

johnmuthu23-Apr-08 9:59

Re: Problem in page Redirect

23-Apr-08 9:59

Thanks for the article sandeep.

The reason why i wanted to avoid is, i am selecting a No of records from a gridview that is in my page, where i use callback mechanism, to avoid page postback. The thing is, i don't render gridview to client side.

So, obviously when F5 is pressed, the checked values will be lost..!!

Muthu.G

Problem in page Redirect

Parameswar Mal21-Apr-08 7:19

Parameswar Mal

21-Apr-08 7:19

Hello Friends,
I have a problem in redirect a page.i m using C#.net 2005 .i hv a dropdown list which is bind data from database Like State when i m selecting an item in dropdownlist then the corrospondin District should be come in the second dropdownlist. butit never comes.. there is a problem comes"The specified URL can not be found" I m writing the code below for beter understand.
I m also set the Autopostback property =true in dropdownlist.

protected void Page_Load(object sender, EventArgs e)
{
if(!IsPostBack)
{
con.Open();
SqlCommand com = new SqlCommand("select State from StateInfo order by StateName asc", con);
dr = com.ExecuteReader();
while (dr.Read() == true)
{
drp_regionname.Items.Add(dr[0].ToString());
}
dr.Close();

}
}

protected void drp_regionname_SelectedIndexChanged(object sender, EventArgs e)
{

string RegionName = drp_regionname.SelectedValue.ToString();
SqlCommand com1 = new SqlCommand("select district from DistrictInfo where StateName ='" + RegionName + "'", con);
con.Open();
dr = com1.ExecuteReader();
while (dr.Read())
{
drp_unitname.Items.Add(dr[0].ToString());
}
dr.Close();
con.Close();

}

This code is running fine in local server but not running in Remote server..

Plz help me.......

Thanks ...

Sandeep Akhare21-Apr-08 19:27

Sandeep Akhare

21-Apr-08 19:27

Could explain where is the problem ?
Where are you redirecting to another page ?
drp_unitname drop down list is not getting populated with items ?

Thanks and Regards
Sandeep

If If you look at what you do not have in life, you don't have anything,
If you look at what you have in life, you have everything... "

Re: Problem in page Redirect

vkrajeesh22-Apr-08 2:24

vkrajeesh

22-Apr-08 2:24

from ur code it seems u r not redirecting ur page anywhere. the same page is posted back.

As far as the URL not found error , check the "REDIRECT" code u have written and see whether the target page u r specifying exists in ur website. could u post the conn string info as well as the redirect section of ur code.

Regards,
Rajeesh
Did u know-Maths Illiteracy affects 9 out of 7 people

Re: Problem in page Redirect

l0kke22-Apr-08 5:51

l0kke

22-Apr-08 5:51

Your code is filling drop down from database on PageLoad, if region name selection changes, it inserts additional data from the db (not clearing previous data from the drop down!, is it what you want?)

I don't see any redirection at all!

However, few tips:
1. in sqlcommand, always use Parameters instead of concatenated strings as a query, to prevent sql injection (security flaw):
SqlCommand com1 = new SqlCommand("select district from DistrictInfo where StateName = @RegionName", con);
com1.Parameters.Add(new SqlParameter("@RegionName", RegionName));

2. be sure you are closing connection to database when you don't need it anymore

3. use 'using' clause when possible, to ensure your IDisposible objects are going to be disposed in all cases (no need to call dr.Close(), as it is going to be called in Dispose() method:
using (dr = com1.ExecuteReader())
{
while (dr.Read())
{
drp_unitname.Items.Add(dr[0].ToString());
}
}

4. use exception handling, try {...} catch {...} blocks, at least in event handlers

Add data to an Access database without binding control(s)

Joseph Marzbani21-Apr-08 6:38

Joseph Marzbani

21-Apr-08 6:38

Hi masters!

I've a table in Access that has 4 columns.
How can I add records to it without having to bind any control(s) (Text Box, Dropdown List, ...).

Re: Add data to an Access database without binding control(s)

Vasudevan Deepak Kumar30-Apr-08 1:51

Vasudevan Deepak Kumar

30-Apr-08 1:51

A preliminary tutorial on insert to MsAccess can be had off from here:

www.codeproject.com/KB/applications/myaspnetguestbook.aspx[^]

Vasudevan Deepak Kumar
Personal Homepage
Tech Gossips

A pessimist sees only the dark side of the clouds, and mopes; a philosopher sees both sides, and shrugs; an optimist doesn't see the clouds at all - he's walking on them. --Leonard Louis Levinson

Unable to hide the Label Column

johnmuthu21-Apr-08 6:21

21-Apr-08 6:21

I am using a gridview where I have a lable bound column to keep unique ids. During DataRowBound event i hide the label column.

int labelColumn = 0;
e.Row.Cells[labelColumn].Visible = false;

I keep the above code snippet in DataRowBound of GridView1.

When try to use the label column value at client side, I am Unable to access the value. If i don't hide the column I am able to access label value.

Now i want to hide the label Column. How could i do?

I even tried by making the lable column width as 0px.

Thanks in advance. Smile | :)

Muthu.G

Ashish Sehajpal21-Apr-08 7:02

21-Apr-08 7:02

pretty simple solution dear

use direct <%# Eval("columnname") % > as argument in javascript function or wherever you need to call the value of that label..... do not use any label or column in specific

cheers !

Ashish Sehajpal

johnmuthu21-Apr-08 9:12

21-Apr-08 9:12

Thanks for the reply dear.

i thing u mean to say, in DataBinding of label (that's in design mode),
for label just use Eval("columnname").

But will that solve the problem of hiding the label field at run time?

Plz be brief in ur ans.

Also how to use it as an arg of js function?

Muthu.G

Ashish Sehajpal22-Apr-08 1:48

22-Apr-08 1:48

using an HTML control is not the solution as per architecture...if there are 1000 records, there will be 1000 html control and every time you will be finding that control via javascript....

passing argument to javascript is very easy

onclick='functionname(<%# Eval("arg1")%>,<%# Eval("arg2")%> ) ;'

you can use any event i.e. onchange , onblur , ondoubleclick etc.....

it will outperform in terms of performance

Ashish Sehajpal

johnmuthu23-Apr-08 10:13

23-Apr-08 10:13

Thanks Ashish. got it...

Muthu.G

P. S. Pundeer21-Apr-08 7:13

P. S. Pundeer

21-Apr-08 7:13

You can use hidden field html server control instead of label.

puranonnet@hotmail.com
www.ibrinte.com

johnmuthu21-Apr-08 9:07

change the default selected value in the asp:DropDown

21-Apr-08 9:07

Thanks a lot, that works fine. Big Grin | :-D

Muthu.G

gottimukkala21-Apr-08 5:25

gottimukkala

21-Apr-08 5:25

Hi All,

I have a page that calls another with parameters (Eg: page2.aspx?show=pdf&w=100&h=200). My page2 contains textboxes and the drop downlist(with default value set to something else), when I enter the page2 I want to set the parameters to my textboxes and dropdown list. I used ddlEmbedDisplay.SelectedValue = show; but its showing the old default value after this statement, Could any one please tell me, my statement is right or wrong.
Any Ideas please!!!

Thanks,
Aruna.G

Re: change the default selected value in the asp:DropDown

Ashish Sehajpal21-Apr-08 7:04

Re: change the default selected value in the asp:DropDown

21-Apr-08 7:04

wrong...

mention the querystring collection instead

use

ddlEmbedDisplay.SelectedValue = request.queryString("show")

cheers !

Ashish Sehajpal

vkrajeesh21-Apr-08 20:14

vkrajeesh

21-Apr-08 20:14

hi Aruna,

From ur query it seems u want to pass a value from one page to another and set that value as the selected Text of a dropdownlist on page 2 when page 2 loads. right?

heres how you can do it.its crude but still.

//Code on page 1
param1 = "Good Morning";
param2 = 300;
Response.Redirect("default2.aspx?param1=" + param1 + "&param2=" + param2.ToString());

//code on page 2
String param1="";
String param2;

param1=request.querystring("param1");
param2=request.querystring("param2").tostring();
DropDownList1.Items.Add(param1);
DropDownList1.Items.Add(param2);
DropDownList1.SelectedIndex = DropDownList1.Items.Count - 1(when new items are added to a dropdownlist they get appended to the end of the list of items.1 denotes the last item,2 would be the second last item etc.)

Hope this helps

Remember Me Cookie

nour12321-Apr-08 4:13

nour123

21-Apr-08 4:13

Hi all...
I have a login form (username and password), and I want to add a checkbox (remember me), how can I perform this cookie using ASP.NET (VB) ?

Thanks alot

Nour Abdel-Salam...
A Trainer and a Web Developer in Jedda Int'l Computer Center(JICC)

Re: Remember Me Cookie

eyeseetee21-Apr-08 4:23

eyeseetee

21-Apr-08 4:23

check this, might help

http://www.startvbdotnet.com/aspsite/forms/cookies.aspx

Re: Remember Me Cookie

nour12323-Apr-08 6:13

nour123

23-Apr-08 6:13

Thank you very much,
Luv you >>>

Rose | [Rose]

Nour Abdel-Salam...
A Trainer and a Web Developer in Jedda Int'l Computer Center(JICC)

Re: Remember Me Cookie

Ashish Sehajpal21-Apr-08 4:25