In Php, how to get float value from a mixed string?

Question

I got a string like:

$str = "CASH55.35inMyPocket";

I want to get 55.35 only.

I tried:

$str = floatval("CASH55.35inMyPocket");
if ($str > 0) {
    echo "Greater_Zero";
} else {
    echo "LessZERO!!";
}
// echo "LessZERO!!";

I also tried:

$str = (float)"CASH55.35inMyPocket";
if ($str > 0) {
    echo "Greater_Zero";
} else {
    echo "LessZERO!!";
}
// echo "LessZERO!!";

According to the Documentation:

Strings will most likely return 0 although this depends on the leftmost characters of the string.

So, flotval and (float) apparently only work if the string is something like: 55.35aAbBcCdDeEfF... but will NOT work if it is like: aAbBcC55.35dDeEfF

is there a way to get the float no matter the position of text?

Answer 1

If you dont want to use regular expressions use filter_var:

$str = "CASH55.35inMyPocket";
var_dump( (float) filter_var( $str, FILTER_SANITIZE_NUMBER_FLOAT, FILTER_FLAG_ALLOW_FRACTION ) ); // float(55.35) 

Answer 2

What you have cannot be casted to a float, because it doesn't look like a float from PHP's perspective. It is possible to grab the value using regex though.

If you are not sure whether there will always be a decimal. And you are trying to get the number regardless of position in the text (as per your question). You could use:

^.*?([\d]+(?:\.[\d]+)?).*?$

Which gets the numeric values from the following strings:

CASH55.35inMyPocket
CASH55inMyPocket
55.35inMyPocket
55inMyPocket
inMyPocket55.35
inMyPocket55

Explanation: http://regex101.com/r/tM8eM0
Demo: http://rubular.com/r/Gw5HTzsejj
PHP demo: https://eval.in/165521

Basically it looks for numbers in the string. And optionally it also check for decimals after that.