In this thread we will discuss in detail about various string functions and manipulations used in php. Let us start with the trim function in php.

trim -- Strip whitespace from the beginning and end of a string.

Syntax : trim(string,charlist)

string - Specifies the string to check

charlist - Specifies which characters to remove from the string. If omitted, all of the following characters are removed:
* "\0" - NULL
* "\t" - tab
* "\n" - new line
* "\x0B" - vertical tab
* "\r" - carriage return
* " " - ordinary white space

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Hi ,
How to convert a string in to array?

Anand

How to use trim for right side also for left side spaces

Hi varghese,

One very simple way to convert any string as array is using "explode" function.

For example if your string like that ->

$vStrVal = "one,two,three,four";
$aArrVal = explode(",",$vStrVal);

It is most commonly used way to do that.

Thanks

__________________
K K Venkata Charya
Success is easy to get but difficult to retain

ltrim - trim used for removing the left side spaces

It will remove the whitespaces on the left side that is it will remove the whitespaces from the beginning of the string.

Let us explain with this example

$str = " have a nice day";
echo ltrim($str);
output : have a nice day (without white spaces / left side spaces)

rtrim - trim used for removing the right side spaces

It will remove the whitespaces on the right side that is it will remove the whitespaces from the end of the string

Let us explain with this example

$str = "Good Morning ";
echo rtrim($str);
output : Good Morning (without white spaces / right side spaces)

What is the difference between the strstr() and stristr()?

Let us discuss about the string function called str_replace()

str_replace() function replaces some characters with some other characters in a string.

This function works by the following rules:

• If the string to be searched is an array, it returns an array
• If the string to be searched is an array, find and replace is performed with every array element
• If both find and replace are arrays, and replace has fewer elements than find, an empty string will be used as replace
• If find is an array and replace is a string, the replace string will be used for every find value

Syntax
str_replace(find,replace,string,count)

Parameter Description
find - Required Specifies the value to find
replace - Required. Specifies the value to replace the value in find
string - Required. Specifies the string to be searched
count - Optional. A variable that counts the number of replacements

Example
<?php
echo str_replace("Evening","Morning","Good Evening");
?>

Output : Good Morning

Hi Venkat_charya,
In explode we have to use any key word but i need to convert a array as each character without any key word.

Varghese,

Like "C language" we can directly refer to the variable with the array.

For example,
$str = "string";
for($i=0;$i<strlen($str);$i++)
echo $str[$i];

The above code will print "string". You can directly refer to the characters with the positions.

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None of us is As Strong as All of us.

strstr is a conceptual integration of strpos above: whereas strpos locates a match and returns the number of its index offset, strstr still locates the first match but doesn't return the number but the whole string from there:
$string='hallo world hallo' ;
print strstr($string,'hallo');

stristr is the same as strstr, but this round case insensitive.

Thanks

__________________
K K Venkata Charya
Success is easy to get but difficult to retain

Let us discuss about the substr()

Substr() - Returns a part of the string

Syntax :
string substr ( string string, int start [, int length] )

Parameters
string - specifies the string
start - specifies the start index
length - specifies the length of the substring

Example :
echo substr("happy birthday",0, 5)
Output: happy

If you not specified the length parameter (parameter 3), returns the string from $start to the end of the string.

Example:
echo substr("happy birthday",6);
Output: birthday

If the $start parameter is a negative number, the position starts from end of the string.

Example:
echo substr("happy birthday",-8);
Output: birthday

echo substr("happy birthday",-8, 5);
Output: birth

If $length is negative, substr( ) counts back from the end of the string to
determine where your substring ends:

Example:
echo substr(’on the way to operating theatre’, 4,-3)
Output: he way to operating thea

Hi Anand

In PHP 5 one function available to split string without loop

<?php

$str = "Hello Friend";

$arr1 = str_split($str);
$arr2 = str_split($str, 3);

print_r($arr1);
print_r($arr2);

?>

output:

Array
(
[0] => H
[1] => e
[2] => l
[3] => l
[4] => o
[5] =>
[6] => F
[7] => r
[8] => i
[9] => e
[10] => n
[11] => d
)

Array
(
[0] => Hel
[1] => lo
[2] => Fri
[3] => end
)

I have a question about how to manipulate php string.
For example, I have a text string:
$vString="
---<updated:12/20/06>---
Updated First
---<updated:12/19/06>---
Updated second";

Now if I want to remove "---<updated:XX/XX/XX>---" and only display:
Updated First
Updated second

how can I do that? Is there a php function can do this?

Thanks

Hi Varghese check this,
ereg_replace("(---<updated: )[0-9]{2}(/)[0-9]{2}(/)[0-9]{2}(>---)","",$vString);

Thanks Senthil It working fine.

Today we will discuss about the strip_tags()

Strip_tags() - It will strip the html and php contents from the given string

Syntax:
string strip_tags ( string $str [, string $allowable_tags] )

Parameters
str

The input string.

allowable_tags

You can use the optional second parameter to specify tags which should not be stripped.

Note: HTML comments are also stripped. This is hardcoded and can not be changed with allowable_tags.

Example
echo strip_tags("Fantastic <b>day!</b>");
Output:

Fantasic day!

$text = '<p>Test paragraph.</p><!-- Comment --> <a href="#fragment">Other text</a>';
echo strip_tags($text, '<p><a>');
Output:

<p>Test paragraph.</p> <a href="#fragment">Other text</a>

Now discuss about addcslashes()

addcslashes() - Returns a string with backslashes in front of the specified characters.

Syntax
addcslashes(string,characters)

Example
$str = "Hello, my name is Kai Jim.";
echo $str."<br />";
echo addcslashes($str,'A..Z')."<br />";
echo addcslashes($str,'a..z')."<br />";
echo addcslashes($str,'a..h');

Output:
Hello, my name is Kai Jim.
\Hello, my name is \Kai \Jim.
H\e\l\l\o, \m\y \n\a\m\e \i\s K\a\i J\i\m.
H\ello, my n\am\e is K\ai Jim.

Note:
Be careful using addcslashes() on 0, r, n and t. In PHP, \0, \r, \n and \t are predefined escape sequences.

What is pack() and unpack() in php?

__________________
K K Venkata Charya
Success is easy to get but difficult to retain

__________________
K K Venkata Charya
Success is easy to get but difficult to retain