JavaScript跨天时间区间（22点至次日9点）判断失效问题排查

云原生阿岚

2026-5-28

Fixing Cross-Day Time Slot Check for Dinner

Ah, I see the issue here—your current logic fails for the Dinner slot because it's a cross-midnight window, and the standard >=/< check doesn't work when set_min (22) is larger than set_max (9). Let's break this down and fix it.

Why the Original Logic Breaks

When you set set_min = 22 and set_max = 9, the condition passintime >= 22 && passintime <9 can never be true. Since passintime is an hour between 0 and 23, there's no value that's both >=22 AND <9. That's why your Dinner slot isn't being detected correctly.

The Solution: Adjust the Check for Cross-Day Slots

We need to handle two cases:

Normal non-cross-day slots (like Lunch and Snack): Use the original >= and < logic.
Cross-day slots (Dinner here): Check if the time is either >= the start time (22) OR < the end time (9).

Here's how to update your check code:

var passintime = new Date(data[i].passintime).getHours();
var isInTargetSlot;

// Check if we're dealing with a cross-day slot
if (set_min > set_max) {
  // Cross-day: time is >= start OR < end
  isInTargetSlot = passintime >= set_min || passintime < set_max;
} else {
  // Normal slot: time is between start (inclusive) and end (exclusive)
  isInTargetSlot = passintime >= set_min && passintime < set_max;
}

if (isInTargetSlot) {
  // Your business code here
}

Alternative: One-Liner Condition

If you prefer a more concise version without the extra variable, you can combine both cases into a single condition:

var passintime = new Date(data[i].passintime).getHours();

if (
  (set_min <= set_max && passintime >= set_min && passintime < set_max) ||
  (set_min > set_max && (passintime >= set_min || passintime < set_max))
) {
  // Your business code here
}