Programming + Errors: September 2012

JavaScript is a very useful language for client side scripting. Often you need to add control dynamically in your page. Sometimes you need customization according to client selection criteria. JavaScript is very handy to fulfill these. There are many ways to add a control dynamically using JavaScript. I would suggest the DOM architecture. Now what is DOM? DOM (document Object Model) is a platform- and language-independent standard that can be used for Dynamic HTML. Using DOM you can traverse both way, parent to child or child to parent. It is also useful for modifying the style sheets. The following code shows how to add a textbox dynamically using JavaScript. Just open a notepad copy and paste the following code, save it as HTML. Then Open it in a browser.

<!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>
<title>Untitled Page</title> 
<script language="javascript" type="text/javascript">
<!--

var NumOfRow=1;

function Button1_onclick()
{
NumOfRow++;

// get the refference of the main Div
var mainDiv=document.getElementById('MainDiv');

// create new div that will work as a container
var newDiv=document.createElement('div');
newDiv.setAttribute('id','innerDiv'+NumOfRow);

//create span to contain the text
var newSpan=document.createElement('span');
newSpan.innerHTML="Enter Your Mail Address ";

// create new textbox for email entry
var newTextBox=document.createElement('input');
newTextBox.type='text';
newTextBox.setAttribute('id','txtAddr'+NumOfRow);

// create remove button for each email adress

var newButton=document.createElement('input');
newButton.type='button';
newButton.value='Remove';
newButton.id='btn'+NumOfRow;

// atach event for remove button click
newButton.onclick=function RemoveEntry() { var mainDiv=document.getElementById('MainDiv');
mainDiv.removeChild(this.parentNode);
}

// append the span, textbox and the button
newDiv.appendChild(newSpan);
newDiv.appendChild(newTextBox);
newDiv.appendChild(newButton);

// finally append the new div to the main div
mainDiv.appendChild(newDiv);

}
// -->
</script>

</head>

<body>
<div id="MainDiv">
Enter Your Mail Address <input id="txtAddr1" type="text" />
<input id="Button1" type="button" value="Add More" onclick="Button1_onclick()" /></div>
</body>
</html>

Here in our web page we have a simple form which includes a div Named “MainDiv”. Inside the div a textbox and a button is included. When you click the button new textbox with a remove button appears. If you click again, another pair is added and so on……

select (select name from source where id = src.parent) as 'Plant', abbreviation, src.name, IFNULL((select sec_to_time(sum(time_to_sec(Duration))) from downtime where category=1 and source =down.source ),sec_to_time(0)) as 'Planned',
IFNULL((select sec_to_time(sum(time_to_sec(Duration))) from downtime where category=2 and source =down.source),sec_to_time(0)) as 'Unplanned',
IFNULL((select sec_to_time(sum(time_to_sec(Duration))) from downtime where category=3 and source =down.source),sec_to_time(0)) as 'StandBy',
IFNULL((select sec_to_time(sum(time_to_sec(Duration))) from downtime where source =down.source),sec_to_time(0)) as 'Total'
from downtime down
inner join category c on down.category = c.id
inner join source src on down.source = src.id
group by abbreviation;

Programming + Errors

Wednesday, September 12, 2012

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Wednesday, September 5, 2012

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