我刚刚将duration_str更新为<?php
$timeslot = [];
$timeslot[] = '07:00-08:00';
$timeslot[] = '07:15-07:30';
$timeslot[] = '07:30-08:30';
$timeslot[] = '10:45-11:45';
$min_time = -1;
$max_time = -1;
$total_minutes = 0;
foreach($timeslot as $slot){
list($start_time,$end_time) = explode("-",$slot);
$start_time = explode(":",$start_time);
$start_time = intval($start_time[0]) * 60 + intval($start_time[1]); // converting to minutes
$end_time = explode(":",$end_time);
$end_time = intval($end_time[0]) * 60 + intval($end_time[1]);// converting to minutes
if($min_time == -1){// or max time for that matter (just basic initialization of these 2 variables)
$min_time = $start_time;
$max_time = $end_time;
$total_minutes += $max_time - $min_time;
}else{
if($start_time >= $max_time) $total_minutes += $end_time - $start_time;
else if($start_time < $max_time && $end_time > $max_time) $total_minutes += $end_time - $max_time;
$min_time = min($min_time,$start_time);
$max_time = max($max_time,$end_time);
}
}
echo intval($total_minutes / 60),":",($total_minutes % 60)," hrs";
，我正在尝试编辑代码。
我有一个简单的代码
typescript我想将3.7.4与interface Test
event: {
queryStringParameters: { [name: string]: string } | null;
}
}
const test:Test = (event) => {
// const { no } = event?.queryStringParameters; //Property 'no' does not exist on type '{ [name: string]: string; } | null'.ts(2339)
const no = event?.queryStringParameters?.no; //It works but I want to use above that.
...
}
一起使用。
它现在可用吗？
答案 0 :(得分：9)
这是因为queryStringParameters可以为null，并且null对象不包含属性no。为此，您需要使用null coalescing operator：
const { no } = event?.queryStringParameters ?? { no: null };
请注意，??运算符目前仅可通过 TypeScript 3.7 + 使用，目前还不是标准的JS运算符。有关更多详细信息，请参见有关TypeScripts存储库的相关讨论：https://github.com/microsoft/TypeScript/issues/26578