Question

我必须编写很多这样的代码：

         if ( !empty($value['fax'])) {
                $temp['fax'] = $value['fax'];
         } else {
            $temp['fax'] = "unknown";
         }

只是想知道是否有更短的版本...

Answer 1

查看a similar answer I wrote on the subject：

def pentaSquares(n):
    squarlist=[]
    pentalist=[]
    squares = lambda x:x*x
    penta = lambda y:y*(3*y-1)//2
    for i in range(n):
        squarlist.append(squares(i))
        pentalist.append(penta(i))
    l=[x for x in squarlist if x in pentalist]
    if l < 4:
        print('there are less than 4 values, input larger n')
    return l

如果您实际上正在检查$temp['fax'] = (!empty($value['fax'])) ? $value['fax'] : 'unknown';或isset()而非is_null()（其中包括empty()，null，false，{{ 1）}）然后在PHP 7中：

Answer 2

PHP7 +解决方案（Null coalesce operator）：

$temp['fax'] = $value['fax'] ?? 'unknown';

Answer 3

使用三元运算符：

$temp['fax'] = !empty($value['fax']) ? $value['fax'] : 'unknown'

如何简化检查null的PHP代码并设置值来替换null？

3 个答案: