A neater way within ksh is to slice the variable and it doesn't spawn a new process. If you know that "te" is to be removed from the begginning and "Id" from the end then it's simply like Scrutinizer wrote:-
however if you just want to trim any two leawding and trailing characters you need to use the wildcard ?:-
Hello,
I have a korn shell string variable
str1 = "A,B,Z"
I would like to create another korn shell string variable
str2 = "letter = 'A' or letter = 'B' or letter = 'Z' "
Please help!
Thanks in advance
an UNIX newbie! (13 Replies)
Hey Guys,
Right i know how to alter a word to begin with a capital letter, i know how to remove unwanted characters and replace them with the relevant character however i don't now if there is a way to do them all in one line.
Code:
echo -n ${string:0:1} | tr a-z A-Z #convert first letter... (4 Replies)
I use otool on OS X to figure out the shared libraries that a binary uses. I run this command:
otool -L /Applications/Vidnik\ 0.13.0/Vidnik.app/Contents/MacOS/Vidnik
And it returns an output similar to this:
/Applications/Vidnik 0.13.0/Vidnik.app/Contents/MacOS/Vidnik:... (10 Replies)
Hi,
I have the string like this ". Start : 06:53:11 - MON JUL 05, 2010"
I need to print the part "06:53:11 - MON JUL 05, 2010"
How i can do this?
Thanks,
Lenova (2 Replies)
Write a shell program to display the position of the right - most character in a given input string.
Example :
Input : RAHUL
Output : L is in the 5th position
also tell me how to count length of string and how to find the position of specific character in left most side. (1 Reply)
Write a shell program to display the position of the right - most character in a given input string.
Example :
Input : RAHUL
Output : L is in the 5th position
also tell me how to count length of string and how to find the position of specific character in left most side.
Homework... (0 Replies)
I want to do the next
"I don't want to go school
because I'm sick today."
I want to join these two line but only when the first line is not more than 20 characters
and ended whit nothing or a comma and the second line not more than 15.
The 20 and the 15 can be change in the script.
I know... (10 Replies)
Hello
Could you help with small script:
How to split string X1 into 3 string
String X1 can have 1 or many strings
X1='A1:B1:C1:D1:A2:B2:C2:D2:A3:B3:C3:D3'
This is output which I want to have:
Z1='A1:B1:C1:D1'
Z2='A2:B2:C2:D2'
Z3='A3:B3:C3:D3' (5 Replies)
i have a string that am looking to extract all characters following 3 consecutiv numbers.
Example my string is J1705PEAN038TDMN, i need to get TDMN
My string can have multiple 3 consecutive numbers, i need what follows last occurance (9 Replies)
Discussion started by: gigagigosu
9 Replies
LEARN ABOUT PHP
empty
EMPTY(3) 1 EMPTY(3)empty - Determine whether a variable is emptySYNOPSIS
bool empty (mixed $var)
DESCRIPTION
Determine whether a variable is considered to be empty. A variable is considered empty if it does not exist or if its value equals FALSE.
empty(3) does not generate a warning if the variable does not exist.
PARAMETERS
o $var
- Variable to be checked
Note
Prior to PHP 5.5, empty(3) only supports variables; anything else will result in a parse error. In other words, the follow-
ing will not work: empty(trim($name)). Instead, use trim($name) == false.
No warning is generated if the variable does not exist. That means empty(3) is essentially the concise equivalent to !isset($var)
|| $var == false.
RETURN VALUES
Returns FALSE if $var exists and has a non-empty, non-zero value. Otherwise returns TRUE.
The following things are considered to be empty:
o "" (an empty string)
o 0 (0 as an integer)
o 0.0 (0 as a float)
o "0" (0 as a string)
o NULL
o FALSE
o array() (an empty array)
o $var; (a variable declared, but without a value)
CHANGELOG
+--------+---------------------------------------------------+
|Version | |
| | |
| | Description |
| | |
+--------+---------------------------------------------------+
| 5.5.0 | |
| | |
| | empty(3) now supports expressions, rather than |
| | only variables. |
| | |
| 5.4.0 | |
| | |
| | Checking non-numeric offsets of strings returns |
| | TRUE. |
| | |
+--------+---------------------------------------------------+
EXAMPLES
Example #1
A simple empty(3) / isset(3) comparison.
<?php
$var = 0;
// Evaluates to true because $var is empty
if (empty($var)) {
echo '$var is either 0, empty, or not set at all';
}
// Evaluates as true because $var is set
if (isset($var)) {
echo '$var is set even though it is empty';
}
?>
Example #2
empty(3) on String Offsets
PHP 5.4 changes how empty(3) behaves when passed string offsets.
<?php
$expected_array_got_string = 'somestring';
var_dump(empty($expected_array_got_string['some_key']));
var_dump(empty($expected_array_got_string[0]));
var_dump(empty($expected_array_got_string['0']));
var_dump(empty($expected_array_got_string[0.5]));
var_dump(empty($expected_array_got_string['0.5']));
var_dump(empty($expected_array_got_string['0 Mostel']));
?>
Output of the above example in PHP 5.3:
bool(false)
bool(false)
bool(false)
bool(false)
bool(false)
bool(false)
Output of the above example in PHP 5.4:
bool(true)
bool(false)
bool(false)
bool(false)
bool(true)
bool(true)
NOTES
Note
Because this is a language construct and not a function, it cannot be called using variable functions.
Note
When using empty(3) on inaccessible object properties, the __isset() overloading method will be called, if declared.
SEE ALSO isset(3), __isset(), unset(3), array_key_exists(3), count(3), strlen(3), The type comparison tables.
PHP Documentation Group EMPTY(3)