如何使用for循环和条件将值插入到php数组中

问题描述：

I wanted to insert values into a php array using conditions like the way below but it is not happening.

Please let me know if there are any other ways to do that since I am getting "undefined offset" error.

$noarray = array();

for ($i=1; $i<=10 ;$i++)
{
    $noarray[]=$i;
    echo $noarray[$i] . "<br/>"; 
}

答

You are adding $i as a value in the $noarray array.

So is you take step by step, when $i == 1 (first step in for) you will add in the first element of array value of the $i (1). Because in php index starts from 0 you will have an array like this: [0 => 1] with only one element. At this step you try to access the array by index $i = 1, but you have only at index 0 value.

I don't know exactly what you try to do, but you mess with index and value.

Probably you want something like this:

$noarray=array();
for ($i=1; $i<=10 ;$i++)
    {
        $noarray[$i] = $i;
        echo $noarray[$i];
        echo"<br/>";       
    }

This way you specify at index $i to add value $i. You can change this if you want.

答

You are trying to access the array key with advance relative to the moment it was actually set.
The correct access to the current key should be as follows:

...
$noarray[] = $i;
echo $noarray[$i - 1];

OR like it was mentioned in the previous answer:

...
$noarray[$i] = $i;
echo $noarray[$i];

答

Try this:

for ( $i = 0; $i <= 10; $i++ ){
    $noarray[] = $i;
    $noarray[0] = 0;
    $noarray[1] = 1;
}

如何使用for循环和条件将值插入到php数组中

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