One of my class' function outputs a text, something from my mysql db. But i couldn't explode() it since explode needs a string parameter. How to change it to a string.
class admin{
//constructor code
public function department_retrieve(){
//some code to retreive $this->old_department
echo $this->old_department;
}
}
$obj = new admin();
$obj->department_retrieve();
$obj->department_retrieve() outputs a text. I want something to explode the text by spaces. What i miss? How to make it a string? Please help.
You can use the casting operators:
$department_string = (string)$obj->department_retrieve();
You can try as like following . If got problem you can inform me...
<?php
class admin{
//constructor code
public function department_retrieve(){
//some code to retreive $this->old_department
return $this->old_department;
}
}
$obj = new admin();
$value = $obj->department_retrieve();
$dataArray = explode(" ","$value");
print_r ($dataArray );
?>
Related
How can I get PHP to evaluate a static variable in double quotes?
I want to do something like this:
log("self::$CLASS $METHOD entering");
I've tried all sorts of {} combos to get the variable value of self::$CLASS, but nothing has worked. I've currently settled with string concatenation but it is a pain to type:
log(self::$CLASS . " $METHOD entering");
Sorry, you can't do that. It only works for simple expressions. See here.
Unfortunately there is no way how to do this yet. Example in one of answers here will not work, because {${self::$CLASS}} will not returns content of self::$CLASS, but will returns content of variable with name in self::$CLASS.
Here is an example, which does not returns myvar, but aaa:
$myvar = 'aaa';
self::$CLASS = 'myvar';
echo "{${self::$CLASS}}";
Use an anonymous identity function stored in a variable. This way you will have $ immediately after {:
$I = function($v) { return $v; };
$interpolated = "Doing {$I(self::FOO)} with {$I(self::BAR)}";
(I am using class constants in this example but this will work with static variables too).
I don’t know the answer to your question, but you can show the class name and method using the __METHOD__ magic constant.
<?php
class test {
public $static = 'text';
public $self = __CLASS__;
// static Method
static function author() {
return "Frank Glück";
}
// static variable
static $url = 'https://www.dozent.net';
public function dothis() {
$self = __CLASS__;
echo <<<TEST
{${!${''}=static::author()}} // works
{$self::author()} // works
{$this->self::author()} // works
${!${''}=self::author()} // works
{${$this->self}}::author()}} // don't works
${${self::author()}} // do/don't works but with notice
${#${self::author()}} // works but with # !
TEST;
}
}
$test = 'test'; // this is the trick, put the Classname into a variable
echo "{$test::author()} {$$test::$url}";
echo <<<HTML
<div>{$test::author()}</div>
<div>{$$test::$url}</div>
HTML;
$test = new test();
$test->dothis();
I know this is an old question but I find it odd that noone has suggested the [sprintf][1] function yet.
say:
<?php
class Foo {
public static $a = 'apple';
}
you would use it with:
echo sprintf( '$a value is %s', Foo::$a );
so on your example its:
log(
sprintf ( ' %s $METHOD entering', self::$CLASS )
);
//define below
function EXPR($v) { return $v; }
$E = EXPR;
//now you can use it in string
echo "hello - three is equal to $E(1+2)";
Just live with the concatenation. You'd be surprised how inefficient variable interpolation in strings can be.
And while this could fall under the umbrella of pre-optimization or micro-optimization, I just don't think you actually gain any elegance in this example.
Personally, if I'm gonna make a tiny optimization of one or the other, and my choices are "faster" and "easier to type" - I'm gonna choose "faster". Because you only type it a few times, but it's probably going to execute thousands of times.
Yes this can be done:
log("{${self::$CLASS}} $METHOD entering");
Say I got some function that run some code and then return something, like this:
function something()
{
//some code
return $some[$whatever];
}
So, if I want to extract the data I generated in the function - the new value for $some, how should I do it? for example this won't do anything:
echo ($some);
Or what am I missing here, please
Since your Function returns a value, You may need to catch & store it inside a variable and then echo the variable if it is a String or do some casting to that effect. Here's an example:
<?php
function something(){
//some code
$whatever = 3;
$some = ["Peace", "Amongst", "All", "Humanity"];
return $some[$whatever];
}
$var = something();
var_dump($var); //<== DUMPS :: "Humanity"
echo $var; //<== ECHOES:: "Humanity"
Test it out here.
Cheers and Good Luck....
You are trying to return a specif key from your array, which wasn't declared. I declared an array for you, and I added the isset to check if the key is existing in the array to prevent any php warnings.
function something($findKey)
{
$some = array('key'=> 123);
if(!isset($some[$findKey])) {
return false;
}
//some code
return $some[$findKey];
}
echo something('key');
This is the class that I have created in PHP
class userinfo
{
public $username;
public $totalscore;
public $userid;
}
The code below is in a finite loop, and i is set to 0 before entering the loop. And the variable user_array is defined to be an array using the following code:
$user_array = array();
(some code here...)
$i++;
$user_array[i] = new userinfo();
$user_array[i]->totalscore = $stattotal;
$user_array[i]->userid = $id;
For some reason I cant understand why this wont work. I need to create an array of objects. And each object must hold three variables. How do I go about doing so ?
Thank you in Adv. for your Help !
Worked fine for me, remember the $ when using variables.
http://phpfiddle.org/main/code/muv-yx6
You must have a dollar sign ($i) before all variables in PHP.
You can use get_class_vars method to get all properties of class
$my_class = new myclass();
$class_vars = get_class_vars(get_class($my_class));
foreach ($class_vars as $name => $value) {
echo "$name : $value\n";
}
SOURCE : http://php.net/manual/en/function.get-class-vars.php
I am trying to do something like this:
//function name
$str = 'bla()';
//make function with string as name
function $str{
echo 'yey';
}
//Call the function by string name
bla();
You could use eval() to attempt this task. But I really do NOT suggest it:
// name of the function
$str = 'bla';
// php code you want to execute inside
$inside = '';
eval("
function $str() { $inside }
");
Or you could also use an anonymous function:
$name = function() {
// code
};
// execution
$name();
Als if you are just trying to call a dynamic function just use call_user_func() like this:
// name of the function
$str = 'bla';
// paramters to the function
$param = array();
call_user_func($str, $param);
But I think you are doing something wrong. This kind of "hacks" are sign of bad application architecture.
References
eval()
call_user_func()
Anonymous functions
I'll suggest you, not to use like this. But if still you want to do this,
<?php
$greet = function($name)
{
printf("Hello %s\r\n", $name);
};
$greet('World');
$greet('PHP');
?>
Check here
And you are required to use PHP 5.3
Whenever a function completes, it RETURNS a value. If no value is set to be returned, 0 is returned.
If you would like to be able to do as you have asked, you could do the following:
function blah($string="Blah"){
return($string);
}
echo blah("Banana"); //echo's Banana
echo blah(); //echo's Blah
$str = blah("Apple"); //Sets $str to Apple
I just simply want to create a function name with a string value.
Something like this:
$ns = 'test';
function $ns.'_this'(){}
test_this();
It of course throws an error.
I've tried with:
function {$ns}.'_this'
function {$ns.'_this'}
but no luck.
Any thoughts?
You can use create_function to create a function from provided string.
Example (php.net)
<?php
$newfunc = create_function('$a,$b', 'return "ln($a) + ln($b) = " . log($a * $b);');
echo "New anonymous function: $newfunc\n";
echo $newfunc(2, M_E) . "\n";
// outputs
// New anonymous function: lambda_1
// ln(2) + ln(2.718281828459) = 1.6931471805599
?>
This is not possible. If all you want to do is, to prefix all functions with some common string, maybe you want to use namespaces?
namespace foo {
function bar() {}
function rab() {}
function abr() {}
}
// access from global namespace is as follows:
namespace {
foo\bar(); foo\rab(); foo\abr();
}
file with function (somefile.php)
function outputFunctionCode($function_name)
{?>
function <?php echo $function_name ?>()
{
//your code
}
<?php }
file with code which "declares" the function:
ob_start();
include("somefile.php");
outputFunctionCode("myDynamicFunction");
$contents = ob_get_contents();
ob_end_clean();
$file = fopen("somefile2.php", "w");
fwrite($file,$contents);
fclose($file);
include("somefile2.php");
It is ugly, but then again, it is an extremely bad idea to declare functions with dynamic names.
using "eval" is not a good practice, but that may serve the purpose similar to your requirements sometimes.
<?php
$ns = 'test';
$funcName = $ns.'_this';
eval("function $funcName(){ echo 1;}");
test_this();
?>
Is this what you are looking for?
<?php
function foo($a) { print 'foo called'.$a; }
$myfunctionNameStr = 'foo';
$myfunctionNameStr(2);
?>
Cause i don't think that you can dynamically construct a function declaration. You can decide at 'runtime' the value of the $myfunctionNameStr though.