Working with Dates: Comparing dates:

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1 Working with Dates: Suppose, we have a date variable $product['releasedate'] with the value of: :00:00. Now we can display this date in different format using the date(); function as shown below: <?php echo date('m-d-y', strtotime($product['releasedate']));?> //Outputs: <?php echo date('m/d/y', strtotime($product['releasedate']));?> //Outputs: 03/01/08 <?php echo date('l, m-d-y', strtotime($product['releasedate']));?> //Outputs: Saturday, 03/01/2008 <?php echo date('f-d-y', strtotime($product['releasedate']));?> //Outputs: March <?php echo date('m-d-y', strtotime($product['releasedate']));?> //Outputs: Mar and so on. The basic concept of this function is: date( format, timestamp ). You can learn more about all the different types of format here: You would need to change your following code portion. <td><?php echo $product['releasedate'];?></td> to one of the examples shown above and change the format part to match the requirement of getting the output as 01-Mar-2008 Comparing dates: We can compare dates in the same manner as we compare the numerical values. The key concept here is that both the dates that we want to compare should be in the same format. Consider the following example: <?php $var = ""; $today = " "; $testdate = " "; if(strtotime($testdate) > strtotime($today)){ $var = "(Future Date)"; }else{ $var = "(Past Date)"; }

2 echo $var; // This will output (Past Date) because is not > than?> Whereas, consider another example: <?php $var = ""; $today = " "; $anotherdate = " "; if(strtotime($anotherdate) > strtotime($today)){ $var = "(Future Date)"; }else{ $var = "(Past Date)"; } echo $var; // This will output (Future Date) because is actually > than ?> Working with arrays: Suppose you own a computer peripheral shop. You have a sales table in your database that records all the sales made in a particular year. You want to display the sales data in your webpage in a table. You would do a select query to get all the sales from the database. Now you have the sales data in $sales variable. To display this in a table, you would do something like: <table> <tr> <th>year</th> <th>keyboard </th> <th>mouse</th> <th>monitor</th> <th>total Sales</th> <th>average Sales</th>

3 </tr> <?php foreach($sales as $sale){ <tr> <td><?php echo " ";?></td> </tr> <?php }?> <td><?php echo $sale['year'];?></td> <td><?php echo $sale['keyboard'];?></td> <td><?php echo $sale['mouse'];?></td> <td><?php echo $sale['monitor'];?></td> <td><?php echo " ";?></td> This would give you a table as follows: (Considering you are in business only since 2014.) Year Keyboard Mouse Monitor Total Sales Average Sales The numerical values of Keyboard, Mouse and Monitor are the number of units of each sold during that particular year. You would like to replace the unit value with the sales price (unit * unit price). You also want to calculate and display the Total Sales and Average Sales for the particular year. You have a unit price array as: $price = array('keyboard' =>'15', 'mouse' =>'12', 'monitor' =>'20'); This means, $price['keyboard'] = 15; $price['mouse'] = 12; $price['monitor'] = 20; Now, you would need to perform some calculation with the data retrieved from the database before displaying it in the table. You can do this as: <table> <tr> <th>year</th>

4 <th>keyboard </th> <th>mouse</th> <th>monitor</th> <th>total Sales</th> <th>average Sales</th> </tr> <?php foreach($sales as $sale){ $keyboardsales = $sale['keyboard']*$price['keyboard']; $mousesales = $sale['mouse']*$price['mouse']; $monitorsales = $sale['monitor']*$price['monitor']; $yearsalesarray = array ($keyboardsales, $mousesales, $monitorsales); $totalsales = array_sum($yearsalesarray); $averagesales = array_sum($yearsalesarray) / count($yearsalesarray) ; <tr> <td><?php echo $sale['year'];?></td> <td><?php echo "$".$keyboardsales ;?></td> <td><?php echo "$".$mousesales ;?></td> <td><?php echo "$".$monitorsales ;?></td> <td><?php echo "$".$totalsales ;?></td> <td><?php echo "$".round($averagesales, 2) ;?></td> //The round($averagesales, 2); rounds the value of $averagesales to 2 decimal places. </tr> <?php }?> You will then have an output as follows: Year Keyboard Mouse Monitor Total Sales Average Sales 2014 $3000 $1800 $3000 $7800 $ $2250 $2400 $5000 $9650 $

5 You can use this example as a reference and display the Sales table in your lab09. Note: In php, you can concatenate (join) strings using a. (dot). For example: <?php $name = "Dakota State University"; echo "Welcome to ".$name." Madison, SD" ; // Outputs :- Welcome to Dakota State University Madison, SD?>