Detailed explanation of the three forms of php array (array) output_PHP tutorial

Copy code The code is as follows:

$bbbb=array("11"=>"aaa","22"=> "bbb");
//Can only output value value but not key
foreach($bbbb as $color)
{
　echo $color;
}
//value Both can output
foreach($bbbb as $key=>$value)
{
echo $key."=>".$value;
}

//Both value and key can be output
while($color=each($bbbb)){
　 echo $color['key'];
}
or
while(list ($key,$value)=each($bbbb)){
echo "$key : $value
";
}

Direct access to array elements:

Copy code The code is as follows:

$arr=array('w'=>'wen ','j'=>'jian','b'=>'bao');
echo($arr['w']),'
';//It works
echo($arr[w]),'
';//It works
echo($arr[0]),'
';//It doesn’t work Function, I don’t know why? ? ?
echo($arr['j']),'
';//It works
echo($arr[j]),'
';// It works
echo($arr[1]),'
';//It doesn't work, I don't know why? ? ?
echo($arr['b']),'
';//It works
echo($arr[b]),'
';// It works
echo($arr[2]),'
';//It doesn't work, I don't know why? ? ?
?>

Output:

Copy code The code is as follows:

wen
wen
jian
jian
bao
bao

Suspicious point:
Accessing associative array elements,
1. Can the "key" in [ ] be accessed without using quotation marks ("")? ? ?
2. Array index access doesn’t work? ? ?

Copy code The code is as follows:

$arr1=array('wen' ,'jian','bao');
echo $arr1[0],'
',$arr1[1],'
',$arr1[2];
?>

Output:

Copy code The code is as follows:

wen
jian
bao

http://www.bkjia.com/PHPjc/327319.htmlwww.bkjia.comtruehttp: //www.bkjia.com/PHPjc/327319.htmlTechArticleCopy the code as follows: $bbbb=array("11"="aaa","22"="bbb "); //Only value can be output but not key foreach($bbbb as $color) { echo $color; } //Both value and key can be output foreach($bb...