php中闭合内的未定义变量

Question

我有Laravel，PHP和Blade

有问题

@for ($i=1; $i <= 12; $i++)
{!!           
    ($substance->consumptions->filter(function($consumption, $key){
        return $consumption->date->month == $i;
    })->sum('quantity'))
!!},
@endfor

不确定的变量：i（查看：/Users/luisalcaras/projects/piba_web/resources/views/index.blade.php）

Answer 1

您必须使用'use'关键字将变量从父范围传递到闭合：

：

@for ($i=1; $i <= 12; $i++)
{!!           
    ($substance->consumptions->filter(function($consumption, $key) use ($i){
        return $consumption->date->month == $i;
    })->sum('quantity'))
!!},
@endfor

希望这有帮助

Answer 2

尝试这个？

@for ($i=1; $i <= 12; $i++)
{!!           
    ($substance->consumptions->filter(function($consumption, $key){
        global $i;
        return $consumption->date->month == $i;
    })->sum('quantity'))
!!},
@endfor