從最後一個數組值刪除逗號

Question

PHP

$meta = get_post_custom($post->ID); 
$images = $meta['img1'][0]; // urls separated with comma 
$images = explode(',', $images); 
foreach ($images as $image) { 
    echo '{image : '.$image.', title : "Credit: x"},'; 
}; 

輸出：

{image : 'http://localhost/slideshow/1.jpg', title : 'Credit: x'}, 
{image : 'http://localhost/slideshow/2.jpg', title : 'Credit: x'}, 
{image : 'http://localhost/slideshow/3.jpg', title : 'Credit: x'}, 
{image : 'http://localhost/slideshow/4.jpg', title : 'Credit: x'}, // last comma, just after } 

我想刪除最後一個評論逗號中輸出。

這正是我試圖得到：

所需的輸出：

{image : 'http://localhost/slideshow/1.jpg', title : 'Credit: x'}, 
{image : 'http://localhost/slideshow/2.jpg', title : 'Credit: x'}, 
{image : 'http://localhost/slideshow/3.jpg', title : 'Credit: x'}, 
{image : 'http://localhost/slideshow/4.jpg', title : 'Credit: x'} 

Answer 1

你有很多的選擇：

// Using rtrim 
$meta = get_post_custom($post->ID); 
$images = $meta['img1'][0]; // urls separated with comma 
$images = explode(',', $images); 
$string = ''; 
foreach ($images as $image) { 
    $string .= '{image : '.$image.', title : "Credit: x"},'; 
}; 
$string = rtrim($string, ','); 
echo $string; 

// Using substring 
$meta = get_post_custom($post->ID); 
$images = $meta['img1'][0]; // urls separated with comma 
$images = explode(',', $images); 
$string = ''; 
foreach ($images as $image) { 
    $string .= '{image : '.$image.', title : "Credit: x"},'; 
}; 
$string = substr($string, 0, -1); 
echo $string; 

// Using implode 
$meta = get_post_custom($post->ID); 
$images = $meta['img1'][0]; // urls separated with comma 
$images = explode(',', $images); 
$stringElements = array(); 
foreach ($images as $image) { 
    stringElements[] = '{image : '.$image.', title : "Credit: x"}'; 
}; 

$string = implode(',', $stringElements); 
echo $string; 

還要考慮使用一種更有效的方式來創建JSON字符串：json_encode。

Answer 2

可以緩衝輸出到變量和解決這樣：

echo rtrim($bufferedData, ','); 

但正如我所看到的，最好使用json functions。

Answer 3

所以你所有的代碼都是關於從你的數據創建JSON的。這將是：

$data = 'http://localhost/slideshow/1.jpg,http://localhost/slideshow/2.jpg,http://localhost/slideshow/3.jpg'; 
$credit = 'x'; 
$result = json_encode(array_map(function($image) use ($credit) 
{ 
    return ['image'=>$image, 'Credit'=>$credit]; 
}, explode(',', $data))); 
//var_dump($result); 

Answer 4

這也許使用RTRIM（）

$images = 'image1.png,image2.png,image3.png'; 
$ex = explode(',', $images); 
foreach ($ex as $image) { 
    $image_string .= "{'image' : '{$image}', 'title' : 'Credit: x'},"; 
} 

print rtrim($image_string, ','); 

以上低於

{'image' : 'image1.png', 'title' : 'Credit: x'}, 
{'image' : 'image2.png', 'title' : 'Credit: x'}, 
{'image' : 'image3.png', 'title' : 'Credit: x'}