Software Bugs and Solutions

Wednesday, 2 May 2012

Check User Stay time in a page using javascript

var time;

window.onload = function() {

// Initialize "time" variable to "0".

time = 0;

}

window.setInterval(calcTime, 1000);

function calcTime() {

// calculate user-stay time

time += 1;

}

// notify a handler the user-stay time as a query string before the page is unloaded.

window.onbeforeunload = function() {

var oRequest = new XMLHttpRequest();

oRequest.open("get", "/handlers/HandlerTest.ashx?"+time, false);

oRequest.send(null);

}

Get Page Name in asp.net

string sPagePath = System.Web.HttpContext.Current.Request.Url.AbsolutePath;
System.IO.FileInfo oFileInfo = new System.IO.FileInfo(sPagePath);
string sPageName = oInfo.Name;

Controls-collection-cannot-be-modified-because-the-control-contains-code-blocks-ie

Server Error in 'ASP.Net' Application.

The Controls collection cannot be modified because the control contains code blocks (i.e. <% ... %>).

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.
Exception Details: System.Web.HttpException: The Controls collection cannot be modified because the control contains code blocks (i.e. <% ... %>).

Cause

While working with one if my applications where I was adding some controls to the head section of my page. Reason, I used the following JavaScript which had the <% %> tags to get the ClientID of a control

<title>Untitled Page</title>

function GetValue()

{

var txt = document.getElementById("<%=TextBox1.ClientID%>");

alert(txt.value);

}

</script>

</head>

As you can see above I have used ASP.Net Server tags to get the ClientID of textbox hence I cannot add controls dynamically to the head section

Solution

Remove the part which has server tags and place it somewhere else if you want to add dynamic controls from code behind

I removed my JavaScript from the head section of page and added it to the body of the page and got it working

Wednesday, 25 April 2012

Check Database Collation

Syntax:

DATABASEPROPERTYEX(Database, Property);

SELECT DATABASEPROPERTYEX('dbname', 'Collation') as Collation ;

Result:

Collation

Latin1_General_CI_AI

To Change Collate

ALTER DATABASE dabasename COLLATE Collatename ;

1)ALTER DATABASE Test COLLATE French_CI_AS ;

2)Right Click database, choose properties -> options

select Collation

Sys.WebForms.PageRequestManagerTimeoutException

when I tried to export an image, i got this error: "Sys.WebForms.PageRequestManagerTimeoutException The server request timed out"

from the Ajax Extension framework. Its occurred because the export operation was relatively long (something like 2 minutes) and the Ajax Extension Callback framework had a timeout.

How to solve this problem?

To solve this problem we can increase the timeout. You can change the timeout time by adding a new property to the script manager control. This property is called AsyncPostBackTimeOut and it can help us to define the number of seconds before the request will throw a request timeout exception.

For example if you want that the timeout will take maximum 10 minutes your code should be look like this:

<asp:ScriptManager ID="ScriptManager1" runat="server" AsyncPostBackTimeOut="600" ></asp:ScriptManager>

Sunday, 22 April 2012

Capitalise the first letter of each word

create function ProperCase(@Text as varchar(8000))

returns varchar(8000)

begin

declare @Reset bit;

declare @Ret varchar(8000);

declare @i int;

declare @c char(1);

select @Reset = 1, @i=1, @Ret = '';

while (@i <= len(@Text))

select @c= substring(@Text,@i,1),

@Ret = @Ret + case when @Reset=1 then UPPER(@c) else LOWER(@c) end,

@Reset = case when @c like '[a-zA-Z]' then 0 else 1 end,

@i = @i +1

return @Ret

end

Result

select dbo.ProperCase('test’)

Test

Get column names and datatypes in particular table using SQL Server

SELECT column_name as ColumnName,

data_type as DataType,

character_maximum_length as MaximumLength

FROM INFORMATION_SCHEMA.COLUMNS

WHERE table_name = 'Employee_Details'

Result:

ColumnName DataType MaximumLength

id bigint NULL

username varchar 50

firstname varchar 50

lastname varchar 50

city varchar 50

designation varchar 50

Salary decimal NULL