如何在codeigniter或php上过滤数组

Question

I have an options table

Option_ID | option_Type | Option_Text
----------|-------------|------------
1         | gender      | Male        
2         | gender      | Female      
3         | color       | black
4         | color       | white
5         | color       | red
6         | color       | blue

And I am getting all rows to my controller. But I want to filter array which is loading database rows as option_type

I can read

foreach($optionList as $row){
    if ($row->gender){ echo "<option value='".$row->id."'>".$row->text."</opiton>}
}

But I dont want if statement. Is there any way filter as color without if statement

Answer 1

If I understand you correctly, you don't mind using an if condition in the solution. You just don't want to needlessly iterate while only echoing a few rows in the array.

I see that you are working with an array of objects, you can cast as array or try to workaround any array functions that choke on objects.

$options=array(
    array('Option_ID'=>1,'option_Type'=>'gender','Option_Text'=>'Male'),
    array('Option_ID'=>2,'option_Type'=>'gender','Option_Text'=>'Female'),
    array('Option_ID'=>3,'option_Type'=>'color','Option_Text'=>'black'),
    array('Option_ID'=>4,'option_Type'=>'color','Option_Text'=>'white'),
    array('Option_ID'=>5,'option_Type'=>'color','Option_Text'=>'red'),
    array('Option_ID'=>6,'option_Type'=>'color','Option_Text'=>'blue')
);

// collect all option_Type values, retain unique values, declare filter as $f
foreach(array_unique(array_column($options,"option_Type")) as $f){
    echo ucfirst($f),": <select name=$f>";
    foreach(array_filter($options,function($a)use($f){if($a["option_Type"]==$f)return $a;}) as $row){
        echo "<option value='",$row["Option_ID"],"'>",$row["Option_Text"],"</option>";
    }
    echo "</select><br><br>";
}

This will ensure every iteration is useful. Demo

---

Non-LINQ Second Attempt (Demo):

array_filter seems to work for me with my subarrays cast as objects.

foreach(array_filter($options,function($a){return $a->option_Type=='gender';}) as $o){
    echo "{$o->Option_Text}<br>";
}

This makes no wasted iterations and displays:

black
white
red
blue