Coding School – Page 22

March 15, 2007

opening file then reading into variable

[problem]

You want to open save the contents of a file, into a variable in PHP.

[/problem]

[solution]

Simple demo on opening and reading contents of files in PHP.

Script under example tab takes filename as a parameter, then opens it read-only and reads contents in data variable.

Then it echoes a header and footer line, with the data in the middle.

[/solution]

[example]

 <?php
 $filename=$argv[1];
 $FH=fopen("$filename","r") or die("could not open $filenamen");
 while(!feof($FH)) { $data.=fgets($FH); }
 fclose($FH);
 echo "###### beginning of $filename ######n";
 echo "$data";
 echo "n###### end of $filename ######n";
 exit(0);
 ?>

Here is a run through:

$ php -q readfiles.php rhyme.txt ###### beginning of rhyme.txt ###### Mary had a little lamb, It was always bleating. ###### end of rhyme.txt ######

[/example]

[reference]

[tags]PHP file handling, PHP Coding School[/tags]

PHP Docs fopen Function

PHP Docs fgets Function

PHP Docs feof Function

PHP Docs fclose Function

[/reference]

March 14, 2007

how to interperse HTML with PHP

[problem]

You want to intersperse HTML with PHP code.

[/problem]

[solution]

Just getting back to basics, this is a very simple demo
of how to implement PHP code along with HTML.

[/solution]

[example]

 <html><head>....
 <body>
 <h1>Hello World</h1>
 <?php if($_GET[runit]) { ?>
 <b>This will get displayed if ?runit=yes is
 appended to the web users request</b>
 <?php } else { ?>
 nothing to see here ... :)
 <?php } ?>

<body><html>

[/example]

[reference]

[tags]Interperse HTML in PHP, PHP Coding School[/tags]

[/reference]

March 14, 2007

working with arrays part two

[problem]

You want to create an array, then traverse it.

[/problem]

[solution]

Following up from part one – working with arrays.

To spin through all elements in our names array, here is the code below.

[/solution]

[example]

 <?php
 $count=count($names);
 for ($i=0;$i<$count;$i++) { print($names[$i]."n"); }
 ?>

Then for our string index array (hash):

 <?php
 while(list($k,$v)=each($addresses)) {
 echo "$k lives at $vn";
 }
 ?>

[/example]

[reference]

[tags]PHP Arrays, PHP Hashes, PHP Coding School[/tags]

PHP Docs on array

[/reference]

March 14, 2007

working with arrays part one

[problem]

You want to work with string index arrays. Sometimes called Hashes.

[/problem]

[solution]

PHP can handle number or string indexed arrays.

Arrays can be initialized in a number of ways. For example:

Basic array assignment and initialization, without specify numbers or strings:

 <?php
 $names[]="joe";
 $names[]="john";
 $names[]="jim";
 ?>

[/solution]

[example]

Specifically assigning values to numbered elements in the names array:

 <?php
 $names[0]="joe";
 $names[1]="john";
 $names[2]="jim";
 ?>

Quicker way to assign values to names array:

$names=array(“joe”,”john”,”jim”);

Assigning values to a string indexed array – or hash (key and value pairs):

 <?php
 $addresses=array(
 "joe" => "1 Marble Street",
 "john" => "12 Marble Street",
 "jim" => "23 Marble Street"
 );
 ?>

[/example]

[reference]

[tags]PHP, Arrays, PHP Coding School[/tags]

PHP Docs on array

[/reference]

March 14, 2007

regular expression with ereg and eregi

[problem]

You want to perform regular expression with PHP.

[/problem]

[solution]

Again PHP implementation of regular expression is very similar to Perl.

In the simpliest form, pattern matching:

 $ php -q<<EOT
 <?php
 $str="hello world";
 if(ereg("world","$str")) {
 echo("got a match");
 }
 ?>
 EOT

got a match

[/solution]

[example]

Similarly eregi operates the same, just it is case insensitive.

$ php -q<<EOT
<?php

$str=”hello world”;
if(eregi(“WORLD”,”$str”)) {
echo(“got a matchn”);
}

?>
EOT

got a match

[/example]

[reference]

[tags]PHP ereg, PHP eregi, PHP Coding School[/tags]

[/reference]

March 13, 2007

string manipulation strlen and chr

[problem]

You want to perform string manipulation with PHP.

[/problem]

[solution]

Following on from the intro post, see the example tab for some more demos on PHP string manipulation.

[/solution]

[example]

Counting the number of characters in a string:

strlen

 $ php -q<<EOT
 <?php
 echo(strlen("Hello World")."n");

?> EOT

Converts an ASCII code to a character:

chr

 $ php -q<<EOT
 <?php
 echo(chr(65)."n");

?> EOT
A

[/example]

[reference]

[tags]PHP strlen, PHP chr, PHP Coding School[/tags]

[/reference]

March 13, 2007

string manipulation substr and trim

[problem]

Substituting and trimming string variables in PHP.

[/problem]

[solution]

Similar to Perl, PHP has an extensive library of functions.

See the example tab for a few simple examples, showing the basic syntax.

[/solution]

[example]

substr

 $ php -q<<EOT
 <?php
 echo(substr("Hello World",0,4)."n");

?> EOT

Hell

trim

 $ php -q<<EOT
 <?php
 echo(trim("    Hello World    ")."n");
 ?>
 EOT
 
 Hello World
 [/example]
 [reference]
 [tags]PHP substr, PHP trim, PHP Coding School[/tags]
  PHP Docs substr Function
 PHP Docs trim Function
 
 [/reference]

January 13, 2007

epoch generation and converting

[problem]

You want to generate the current epoch offset for UNIX. The count forward since 8am on 1st Jan 1970.

Or conversely you want to see the date and time, for a given epoch offset.

[/problem]

[solution]

You can use perl’s mktime or localtime – or just use my tools below.

[/solution]

[example]

Either enter epoch:

Or enter the date (plus time)

day	month	year
— select day — 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31	— select month — Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec	— select year — 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049
hr	mins	secs
— select hour — 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23	— select mins — 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59	— select secs — 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59

epoch offset or date will appear here

[/example]

[reference]

[tags]epoch, unix, 2038[/tags]

techno park epoch year 2038 problem

[/reference]

January 9, 2007

Free online vertical text image creator

Enter the text to super-impose here and your colours

Background
R:
G:
B:

Foreground
R:
G:
B:

label:

image will appear here

If you want to see the code here it is | Free online vertical text image creator

November 29, 2006

Vertical label creation

[problem]

You want to generate a vertical image, with text over the top.

[/problem]

[solution]

Here is some code I wrote, which is used extensively on my sites:

[/solution]

[reference]

Give it a blast on this site, like this: http://coding-school.com/common/label-up.php?label=your+text+here

Automatically calculates size required. You can also add font=# – where # is 1 to 5, like this:

http://coding-school.com/common/label-up.php?label=your+text+here&font=3

I’ve now created an online tool, using this code

[/reference]

[tags]Image, PHP[/tags]