Displaying class variable

[lerro]

I need some help.

How do i echo out the variable contained in a class?

I have a variable that has been defined in a class

Then, within a function in that class, it has been assigned a value.

Now, i want to output the value in that variable onto screen.

I tried

$object = new className;
$object->varName;

echo $object;

then

echo $varName;

then

echo varName;

but all seem to fail

[cahva]

You missed the most obvious which is:

echo $object->varName;

[lerro]

Thanks, that solved the problem.

But i ran into another problem. The value that is output is the default value of $varName

But within a function of the class, the value of the variable has been changed to something else which is the value i wish to display.

How do i go about displaying the new value of the variable set by the function?

Note that the function also has parameters, so i cannot just do

echo $object->function->varName;

[halojoy]

If you get the default value
is because your function has not changed it.

Use:
$this->varName = 'value';

<?php

Class myclass{

var $varName = 'default';

function change(){

      $this->varName = 'new value';

}

}
////

$obj = new myclass();
$obj->change();
echo $obj->varName; // should return 'new value'

?>

[lerro]

Thanks. That solved the problem.

So, if i want to insert data into the database using that same variable, is this the right way to also do it within the function

$query = "INSERT INTO TableName
(item_id,...,....,)
VALUES ($this->varName,...,...,)";

and is there a difference if i enclose it with apostrophe marks

('$this->varName',...,...,)";

and when i just leave it like this

($this->varName,...,...,)";

as someone said that these marks ' '
tell php to output it as it is, i wasn't sure if that makes any difference for a variable while being input into a database as when i tested, they both seemed to output the variable value

[Kudose]

It's called variable interpolation.

This occurs within double quotes (and Heredoc).

i.e.

$hello = "world";
echo $hello; // world
echo '$hello'; // $hello
echo "$hello"; // world

See http://php.net/manual/en/language.types.string.php

[bradgrafelman]

Actually, variable interpolation is a whole other topic altogether.

The quotes in your example, lerro, are part of the SQL query. Just as in PHP, string values must be surrounded by quotes (normally single quotes) in a SQL query. Thus, if $this->varName contains a string value, then it must be surrounded in quotes inside the SQL query.

[lerro]

Thanks,

Since a string requires quotation marks, do the single quotations in sql matter if the variable holds an integer?

Or does it just ignore whether or not quotations are used?

[bradgrafelman]

The only quotation marks that matter are the ones called the string delimiters. Those are the outer-most quotes that surround the string. Any quote - single or double - inside that string is just another character within the string, no different than a period or a number or anything else.

See the manual page Kudose linked to for more information about strings and delimiters.

[lerro]

Thanks