FIND the position of the FIRST occurrence of a of a substring in a STRING.
<?php
int stripos ( str $haystack , mix $needle [, int $offset = 0 ] )
where,
$haystack = The input STRING to search in
$needle = The needle to be found
$offset = The position where the search will start
?>
EXERCISE
<?php
$str_hp = 'Estou procurando uma agulha
em um palheiro! (UM TRABALHO DIFÍCIL)';
$str_np = 'um';
$int_ap = stripos($str_hp, $str_np);
echo 'A primeira ocorrência de [' . $str_np . ']
<br><br> em, "' . $str_hp . '"
<br><br> é verificada na posição [' . $int_ap . ']';
echo '<br><br><br><br>';
$str_he = "I'm looking for a needle
in a haystack! (A HARD WORK)";
$str_ne = 'A';
$int_ae = stripos($str_he, $str_ne);
echo 'The first occurrence of [' . $str_ne . ']
<br><br> in, "' . $str_he . '"
<br><br> is found at position [' . $int_ae . ']';
?>
EXERCISE
<?php
$str_hpx2 = "I'm looking for a needle
in a haystack! (A HARD WORK)";
$str_np2 = 'haystack';
$off_p2 = -50;
$int_ap22 = stripos($str_hpx2, $str_np2, $off_p2);
echo $str_hpx2;
echo '<br><br><br>The first occurrence of ' . $str_np2
. ', is found at ' . $int_ap22 . ', in relation to the position '
. $off_p2 . '<br><br>' . $str_hpx2 . '<br><br>';
?>
EXERCISE
<?php
$str_hpx3 = "I'm looking for a needle
in a haystack! (A HARD WORK)";
$str_np3 = 'HAYSTACK';
$off_p3 = -50;
$int_ap32 = stripos($str_hpx3, $str_np3, $off_p3);
echo $str_hpx3;
echo '<br><br><br>The first occurrence of ' . $str_np3
. ', is found at ' . $int_ap32 . ', in relation to the position '
. $off_p3 . '<br><br>' . $str_hpx3 . '<br><br>';
?>
EXERCISE
<?php
var_dump(stripos("test string", "TEST"));
echo '<br><br>';
var_dump(stripos("test string", "strIng"));
echo '<br><br>';
var_dump(stripos("test string", "stRin"));
echo '<br><br>';
var_dump(stripos("test string", "t S"));
echo '<br><br>';
var_dump(stripos("test string", "G"));
echo '<br><br>';
var_dump(stripos("te".chr(0)."st", chr(0)));
echo '<br><br>';
var_dump(stripos("tEst", "test"));
echo '<br><br>';
var_dump(stripos("teSt", "test"));
echo '<br><br>';
var_dump(stripos("", ""));
echo '<br><br>';
var_dump(stripos("a", ""));
echo '<br><br>';
var_dump(stripos("", "a"));
echo '<br><br>';
var_dump(stripos("a", " "));
echo '<br><br>';
var_dump(stripos("a", "a"));
echo '<br><br>';
var_dump(stripos("", 1));
echo '<br><br>';
var_dump(stripos("", false));
echo '<br><br>';
var_dump(stripos("", true));
echo '<br><br>';
var_dump(stripos("a", 1));
echo '<br><br>';
var_dump(stripos("a", false));
echo '<br><br>';
var_dump(stripos("a", true));
echo '<br><br>';
var_dump(stripos("1", 1));
echo '<br><br>';
var_dump(stripos("0", false));
echo '<br><br>';
var_dump(stripos("1", true));
echo '<br><br>';
var_dump(stripos("\\\\a", "\\a"));
?>
EXERCISE
<?php
/* Test stripos() function by passing
* single quoted strings to 'haystack'
* & 'needle' arguments */
echo "Testing stripos() function:
with single quoted strings.<br>";
$haystack = 'Hello,\t\n\0\n
$&!#%\o,()*+-./:;<=>?@hello123456he \x234 \101 ';
$needle = [
//regular strings
'l',
'L',
'HELLO',
'hEllo',
//escape characters
'\t',
'\T',
' ',
'\n',
'\N',
'
', //new line
//nulls
'\0',
NULL,
null,
//boolean false
FALSE,
false,
//empty string
'',
//special chars
' ',
'$',
' $',
'&',
'!#',
'%\o',
'\o,',
'()',
'*+',
'+',
'-',
'.',
'.;',
'.;',
':;',
';',
'<=>',
'>',
'=>',
'?',
'@',
'@hEllo',
'12345',
//decimal numeric string
'\x23',
//hexadecimal numeric string
'#',
//hexadecimal numeric string
'\101',
//octal numeric string
'A',
'456HEE',
//numerics + chars
42,
//needle as int(ASCII value of '*')
$haystack
//haystack as needle
];
/* loop through to get the position
of the needle in haystack string */
$count = 1;
for($index=0; $index<count($needle); $index++) {
echo "<br><br>Iteration: $count<br>";
var_dump( stripos($haystack, $needle[$index]) );
var_dump( stripos($haystack, $needle[$index], $index) );
$count++;
}
?>
EXERCISE
<?php
/* Test stripos() function by passing
* multi-line heredoc string for
* haystack and
* with various needles & offsets
*/
echo "Testing stripos() function: with heredoc strings.<br>";
echo "<br><br>With heredoc string containing multi lines:<br>";
$multi_line_str = <<<EOD
Example of string
spanning multiple lines
using heredoc syntax.
EOD;
var_dump( stripos($multi_line_str, "ing", 0) );
echo '<br><br>';
var_dump( stripos($multi_line_str, "ing", 15) );
echo '<br><br>';
var_dump( stripos($multi_line_str, "ing", 22) );
echo '<br><br>';
var_dump( stripos($multi_line_str, "") );
echo '<br><br>';
var_dump( stripos($multi_line_str, " ") );
?>
EXERCISE
<?php
/* Test stripos() function by passing
* heredoc string containing
* special chars for haystack
* and with various needles & offsets
*/
echo "Testing stripos() function: with heredoc strings.<br>";
echo "<br><br>With heredoc string containing special chars:<br>";
$special_chars_str = <<<EOD
Ex'ple of h'doc st'g, contains
$#%^*&*_("_")!#@@!$#$^^&$*(special)
chars.
EOD;
var_dump( stripos($special_chars_str, "Ex'ple", 0) );
echo '<br><br>';
var_dump( stripos($special_chars_str, "!@@!", 23) );
echo '<br><br>';
var_dump( stripos($special_chars_str, '_') );
echo '<br><br>';
var_dump( stripos($special_chars_str, '("_")') );
echo '<br><br>';
var_dump( stripos($special_chars_str, "$*") );
echo '<br><br>';
var_dump( stripos($special_chars_str, "$*", 10) );
echo '<br><br>';
var_dump( stripos($special_chars_str, "(special)") );
?>
EXERCISE
<?php
/* Test stripos() function by passing
* heredoc string containing
* escape chars for haystack
* and with various needles & offsets
*/
echo "Testing stripos() function:
with heredoc strings.<br>";
echo "<br><br>With heredoc string
containing escape characters:<br>";
$control_char_str = <<<EOD
Hello, World\n
Hello\tWorld
EOD;
var_dump( stripos($control_char_str, "\n") );
echo '<br><br>';
var_dump( stripos($control_char_str, "\t") );
echo '<br><br>';
var_dump( stripos($control_char_str, "\n", 12) );
echo '<br><br>';
var_dump( stripos($control_char_str, "\t", 15) );
?>
EXERCISE
<?php
/* Test stripos() function by passing
* heredoc string containing quotes
* for haystack
* and with various needles & offsets
*/
echo "Testing stripos() function:
with heredoc strings.<br>";
echo "<br><br>With heredoc string
containing quote & slash chars:<br>";
$quote_char_str = <<<EOD
it's bright,but i cann't see it.
"things in double quote"
'things in single quote'
this\line is /with\slashs
EOD;
var_dump( stripos($quote_char_str, "line") );
echo '<br><br>';
var_dump( stripos($quote_char_str, 'things') );
echo '<br><br>';
var_dump( stripos($quote_char_str, 'things', 0) );
echo '<br><br>';
var_dump( stripos($quote_char_str, "things", 20) );
?>
EXERCISE
<?php
/* Test stripos() function by passing
* empty heredoc string for haystack
* and with various needles & offsets
*/
echo "Testing stripos() function: with heredoc strings.<br>";
echo "<br><br>With empty heredoc string:<br>";
$empty_string = <<<EOD
EOD;
var_dump( stripos($empty_string, "") );
try {
stripos($empty_string, "", 1);
} catch (ValueError $exception) {
echo $exception->getMessage() . "<br>";
}
var_dump( stripos($empty_string, FALSE) );
echo '<br><br>';
var_dump( stripos($empty_string, NULL) );
?>
EXERCISE
<?php
/* Test stripos() function with
* strings containing repetitive chars
* for haystak
* and with various needles & offsets
*/
echo "Testing stripos() function:
strings repetitive chars.<br>";
$haystack = "aBAbaBAbaBabAbAbaBa";
$needles = [
"aba",
"aBA",
"ABA",
"Aba",
"BAb",
"bab",
"bAb",
"BAB"
];
/* loop through to consider various
offsets in getting the position
of the needle in haystack string */
$count = 1;
for($index = 0; $index < count($needles); $index++) {
echo "<br><br>Iteration: $count<br>";
for($offset = 0; $offset <= strlen($haystack); $offset++ ) {
var_dump( stripos($haystack, $needles[$index], $offset) );
}
$count++;
}
?>
EXERCISE
<?php
/* Test stripos() function with
* unexpected inputs for 'needle' and
* an expected type of input for
* 'haystack' argument
*/
echo "Testing stripos() function with
unexpected values for needle.<br>";
//get an unset variable
$unset_var = 'string_val';
unset($unset_var);
//defining a class
class sample {
public function __toString() {
return "object";
}
}
//getting the resource
$file_handle = fopen(__FILE__, "r");
$haystack = "string 0 1 2 -2 10.5 -10.5
10.5e10 10.6E-10 .5
array true false object \"\" null Resource";
// array with different values
$needles = array (
// integer values
0,
1,
12345,
-2345,
// float values
10.5,
-10.5,
10.1234567e10,
10.7654321E-10,
.5,
// array values
array(),
array(0),
array(1),
array(1, 2),
array('color' => 'red', 'item' => 'pen'),
// boolean values
true,
false,
TRUE,
FALSE,
// objects
new sample(),
// empty string
"",
'',
// null values
NULL,
null,
// resource
$file_handle,
// undefined variable
@$undefined_var,
// unset variable
@$unset_var
);
// loop through each element of the
// 'needle' array to check the working of stripos()
$counter = 1;
for($index = 0; $index < count($needles); $index ++) {
echo "<br><br>Iteration: $counter<br>";
try {
var_dump( stripos($haystack, $needles[$index]) );
} catch (TypeError $e) {
echo $e->getMessage(), "<br>";
}
$counter ++;
}
fclose($file_handle);
//closing the file handle
?>
EXERCISE
<?php
/* Test stripos() function with
* unexpected inputs for 'haystack'
* and 'needle' arguments */
echo "Testing stripos() function with
unexpected values for
haystack and needle.<br>";
// get an unset variable
$unset_var = 'string_val';
unset($unset_var);
// defining a class
class sample {
public function __toString() {
return "object";
}
}
//getting the resource
$file_handle = fopen(__FILE__, "r");
// array with different values
$values = array (
// integer values
0,
1,
12345,
-2345,
// float values
10.5,
-10.5,
10.5e10,
10.6E-10,
.5,
// array values
array(),
array(0),
array(1),
array(1, 2),
array('color' => 'red', 'item' => 'pen'),
// boolean values
true,
false,
TRUE,
FALSE,
// objects
new sample(),
// empty string
"",
'',
// null values
NULL,
null,
// resource
$file_handle,
// undefined variable
@$undefined_var,
// unset variable
@$unset_var
);
// loop through each element of the
// array and check the working of stripos()
$counter = 1;
for($index = 0; $index < count($values); $index ++) {
echo "<br><br>Iteration: $counter<br>";
$haystack = $values[$index];
try {
var_dump( stripos($values[$index], $values[$index]) );
} catch (Error $e) {
echo get_class($e) . ": " . $e->getMessage(), "<br>";
}
try {
var_dump( stripos($values[$index], $values[$index], 1) );
} catch (Error $e) {
echo get_class($e) . ": " . $e->getMessage(), "<br>";
}
$counter ++;
}
?>
EXERCISE
<?php
/* Test stripos() function with null
* terminated strings for 'haystack'
* argument in order to check the binary safe
*/
echo "Test stripos() function: binary safe.<br>";
$haystacks = array(
"Hello".chr(0)."World",
chr(0)."Hello World",
"Hello World".chr(0),
chr(0).chr(0).chr(0),
"Hello\0world",
"\0Hello",
"Hello\0"
);
for($index = 0; $index < count($haystacks); $index++ ) {
var_dump( stripos($haystacks[$index], "\0") );
echo '<br><br>';
var_dump( stripos($haystacks[$index], "\0", $index) );
}
?>
EXERCISE
<?php
/* Test stripos() function with null
* terminated strings for 'needle'
* argument in order to check binary safe
*/
echo "Test stripos() function: binary safe.<br>";
$haystack = "\0Hello\0World\0";
$needles = array(
"Hello".chr(0)."World",
chr(0)."Hello World",
"Hello World".chr(0),
chr(0).chr(0).chr(0),
"Hello\0world",
"\0Hello",
"Hello\0"
);
for($index = 0; $index < count($needles); $index++ ) {
var_dump( stripos($haystack, $needles[$index]) );
echo '<br><br>';
var_dump( stripos($haystack, $needles[$index], $index) );
}
?>
EXERCISE
<?php
/* Test stripos() function by passing
* double quoted strings for 'haystack'
* & 'needle' arguments */
echo "Testing stripos() function:
with double quoted strings.<br>";
$haystack = "Hello,\t\n\0\n
$&!#%\o,()*+-./:;<=>?@hello123456he \x234 \101 ";
$needle = array(
//regular strings
"l",
"L",
"HELLO",
"hEllo",
//escape characters
"\t",
"\T",
//invalid input
" ",
"\n",
"\N",
//invalid input
"
", //new line
//nulls
"\0",
NULL,
null,
//boolean false
FALSE,
false,
//empty string
"",
//special chars
" ",
"$",
" $",
"&",
"!#",
"%\o",
"\o,",
"()",
"*+",
"+",
"-",
".",
".;",
":;",
";",
"<=>",
">",
"=>",
"?",
"@",
"@hEllo",
"12345",
//decimal numeric string
"\x23",
//hexadecimal numeric string
"#",
//respective ASCII char of \x23
"\101",
//octal numeric string
"A",
//respective ASCII char of \101
"456HEE",
//numerics + chars
$haystack
//haystack as needle
);
/* loop through to get the position
of the needle in haystack string */
$count = 1;
for($index=0; $index<count($needle); $index++) {
echo "<br><br>Iteration: $count<br>";
var_dump( stripos($haystack, $needle[$index]) );
var_dump( stripos($haystack, $needle[$index], $index) );
$count++;
}
?>
EXERCISE
<?php
echo "Testing stripos() function: error conditions.<br>";
echo "<br><br>Offset beyond the end of the string:<br>";
try {
stripos("Hello World", "o", 12);
} catch (ValueError $exception) {
echo $exception->getMessage() . "<br>";
}
echo "<br><br>Offset before the start of the string:<br>";
try {
stripos("Hello World", "o", -12);
} catch (ValueError $exception) {
echo $exception->getMessage() . "<br>";
}
?>