How do I order an array from a number in an array item?

I have the following code:

			// check if the file exists
			if (file_exists ('sys/data/online.txt'))
			{
				$read = file ('sys/data/online.txt');
				
				// read the online file
				foreach ($read as $line)
				{
					$item = explode ("\t", $line);
					
					if (isset ($end_data))
					{
						$end_data .= $this-> disp_name ($item[0]) . '<br />';
						
					}
					else
					{
						$end_data = $this-> disp_name ($item[0]) . '<br />';
						
					}
					
				}
				if (isset ($end_data))
				{
					return $end_data;
					
				}
			}

PHP:

It makes an array from a file by lines, then makes another array by separating each array item into another array with tabs. I want to order the names by the timestamp. How would I go about doing this. I have no idea how to even start this.

 

would probably just order by dumping it into a db and letting that do it for me.

if it's a pure linux timestamp though, can just use a bubblesort / any of the sorting algorithms to do it

 

Ok I figured it out. I had to change my previous code to this:

			// check if the file exists
			if (file_exists ('sys/data/online.txt'))
			{
				$read = file ('sys/data/online.txt');
				
				// read the online file
				foreach ($read as $line)
				{
					$item = explode ("\t", $line);
					
					if (!isset ($end_data))
					{
						$end_data = array();
						
					}
						$end_data[$item[1]] = $this-> disp_name ($item[0]);
						
					
				}
				if (isset ($end_data))
				{
					ksort ($end_data);
					
					$end_data = array_reverse ($end_data);
					
					foreach ($end_data as $key => $disp_name)
					{
						if (isset ($result))
						{
							$result .= '<li>' . $disp_name . '</li>';
							
						}
						else
						{
							$result = '<li>' . $disp_name . '</li>';
						
						}
						
					}
					
					return '<ul class="onlinelist">' . $result . '</ul>';
					
				}
			}

PHP: