PHP Array: Exercise-44 with Solution
Write a PHP a function to remove a specified duplicate entry from an array.
Sample Solution:
PHP Code:
Sample Output:
Array
[
[0] => 4
[1] => 5
[2] => 6
[3] => 7
[4] => 4
[6] => 8
]
Flowchart:
PHP Code Editor:
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PHP: Tips of the Day
PHP: How to pass an array within a query string?
Submitting multi-value form fields, i.e. submitting arrays through GET/POST vars, can be done several different ways, as a standard is not necessarily spelled out.
Three possible ways to send multi-value fields or arrays would be:
- ?cars[]=Saab&cars[]=Audi [Best way- PHP reads this into an array]
- ?cars=Saab&cars=Audi [Bad way- PHP will only register last value]
- ?cars=Saab,Audi [Haven't tried this]
Form Examples
On a form, multi-valued fields could take the form of a select box set to multiple:
Volvo
Saab
Mercedes
[NOTE: In this case, it would be important to name the select control some_name[], so that the resulting request vars would be registered as an array by PHP]
or as multiple hidden fields with the same name:
NOTE: Using field[] for multiple values is really poorly documented. I don't see any mention of it in the section on multi-valued keys in Query string - Wikipedia, or in the W3C docs dealing with multi-select inputs.
UPDATE
As commenters have pointed out, this is very much framework-specific. Some examples:
Query string:
?list_a=1&list_a=2&list_a=3&list_b[]=1&list_b[]=2&list_b[]=3&list_c=1,2,3
Rails:
"list_a": "3",
"list_b":[
"1",
"2",
"3"
],
"list_c": "1,2,3"
Angular:
"list_a": [
"1",
"2",
"3"
],
"list_b[]": [
"1",
"2",
"3"
],
"list_c": "1,2,3"
[Angular discussion]
Maintaining order: One more thing to consider is that if you need to maintain the order of your items [i.e. array as an ordered list], you really only have one option, which is passing a delimited list of values, and explicitly converting it to an array yourself.
Ref : //bit.ly/2FGfPLj
This example is just an alternative.