How to loop through an associative array and get the key

Question

My associative array     arr   array     1   gt   Value1      2   gt   Value2      10   gt   Value10       Using the following code   v is filled with  arr s values   foreach  arr as  v       echo  v         Value1  Value2  Value10      How do I get  arr s keys instead    foreach             echo  k         1  2  10

User · Answer

If you use array keys    PHP will give you an array filled with just the keys    keys   array keys  arr   foreach  keys as  key        echo  key       Alternatively  you can do this   foreach  arr as  key   gt   value        echo  key

User · Answer

I use the following loop to get the key and value from an associative array  foreach   array as  key   gt   value      echo   lt p gt  key    value lt  p gt

User · Answer

If you use nested foreach   function  outer array s keys print again and again till inner array values end    lt  php    myArray     key 1    gt    value 1    value12                 key 2    gt    value 2    value22                  key 3    gt    value 3    value32                   keysOfMyArray   array key  myArray    for   x   0   x  lt  count  myArray    x            print   t   keysOfMyArray  x    t t  implode   t t   myArray  keysOfMyArray  x     n         gt

User · Answer

While arguably being less clear this method is faster by roughly a factor of roughly 3 5  At least on the box I used to test    foo   array      1   gt   Value1       2   gt   Value2       10   gt   Value10     while  bar   each  foo        echo  bar 0        gt       bar 1       I would imagine that this is due to the fact the foreach copies the entire array before iterating over it

User · Answer

foreach  array as  k   gt   v    Where  k is the key and  v is the value  Or if you just need the keys use array keys

User · Answer

Use  key   gt   val to get the keys    lt  php   arr   array      1   gt   Value1       2   gt   Value2       10   gt   Value10       foreach   arr as  key   gt   val       print   key n        gt

User · Answer

You can do   foreach   arr as  key   gt   value     echo  key      As described in PHP docs

User · Answer

Nobody answered with regular for loop  Sometimes I find it more readable and prefer for over foreach So here it is    array   array  key1    gt   value1    key2    gt   value2       keys   array keys  array    for  i 0   i  lt  count  keys      i        echo  keys  i           array  keys  i       n           prints    key1 value1   key2 value2

User · Answer

lt  php  names   array  firstname   gt  maurice                   lastname   gt  muteti                    contact   gt  7844433339     foreach   names as  name   gt   value        echo  name      value   lt  br gt       print r  names     gt

User · Answer

foreach  arr as  key  gt  value       echo  key         key

User · Answer

Oh I found it in the PHP manual   foreach   array as  key   gt   value       statement        The current element s key will be assigned to the variable  key on each loop

User · Answer

The following will allow you to get at both the key and value at the same time   foreach   arr as  key   gt   value      echo  key

[php] How to loop through an associative array and get the key?

Examples related to php

Examples related to loops

Examples related to associative-array