如何写if来求工作时间

[cyyjm]

我想求取工作时间，
对于小于8点的时间，统一输出8点00，
对于时间是8:00-12:00，就输出输入的时间参数，
对于时间是12:01-14:30的，就输出12:00，
对于时间为14:31-17:30的，就输出输入的时间参数，
对于17:30以后的时间，就输出17:30.

我写了if语句，写得不好，请大家指教一下。谢谢。

function returnRealWorkTime(t_hour,t_min) {
    var correctHour=0,correctMin=0;
    if(t_hour < 8){correctHour = 8;correctMin= 0;}
    else if(8 <= parseInt(t_hour) < 12){correctHour = t_hour;correctMin= t_min;}
    else if(12<= parseInt(t_hour) < 14){correctHour = 12;correctMin= 0;}
    else if(parseInt(t_hour)=14 && parseInt(t_min) < 30){correctHour = 12;correctMin= 0;}
    else if(parseInt(t_hour)=14 && parseInt(t_min) >= 30 ){correctHour = t_hour;correctMin= t_min;}
    else if( 14<parseInt(t_hour)<=17 && parseInt(t_min) <= 30){correctHour = t_hour;correctMin= t_min;}
    else if(parseInt(t_hour)=17 && parseInt(t_min) > 30){correctHour = 17;correctMin= 30;}
    else {correctHour = 17;correctMin= 30;}
    return correctHour + ':' + correctMin;

}
var x6 = returnRealWorkTime(14,15);  //想输出12:00，但输出14:15
var x7 = returnRealWorkTime(12,39);   //想输出12:00，但输出12:39
var x8 = returnRealWorkTime(18,39);  //想输出17:30，但输出18:39

[天际的海浪]

function returnRealWorkTime(t_hour,t_min) {
	var t = t_hour*100+t_min;
	if (t < 800) return "8:00";
	if (t > 1200 && t <1430) return "12:00";
	if (t > 1730 ) return "17:30";
	return t_hour + ':' + (t_min>9?"":"0") + t_min;
}

[scscms太阳光]

    function returnRealWorkTime(h, m) {
        if (h > 17 || h === 17 && m > 30) {
            return '17:30'
        } else if (h > 14 || h === 14 && m > 30) {
            return h + ':' + ('0' + m).slice(-2)
        } else if (h > 11) {
            return '12:00'
        } else if (h > 7) {
            return h + ':' + ('0' + m).slice(-2)
        } else {
            return '8:00'
        }
    }
    for (let h = 0; h < 24; h++) {
        for (let m = 0; m < 60; m++) {
            console.log(h + ':' + m, returnRealWorkTime(h, m))
        }
    }

[前端_小菜鸟]

function returnRealWorkTime(t_hour, t_min) {
            var correctHour = 0, correctMin = 0;
            if (t_hour < 8) { correctHour = 8; correctMin = 0; }
            else if (parseInt(t_hour) < 12) { 
                correctHour = t_hour; correctMin = t_min; 
            }
            else if (parseInt(t_hour) < 14) {
                correctHour = 12; correctMin = 0;
            }
            else if (parseInt(t_hour) == 14 && parseInt(t_min) < 30) {
                correctHour = 12; correctMin = 0;
            } else if (parseInt(t_hour) < 17) {
                correctHour = t_hour; correctMin = t_min;
            } else if (parseInt(t_hour) == 17 && parseInt(t_min) <= 30) { 
                correctHour = t_hour; correctMin = t_min; 
            }else {
                correctHour = 17; correctMin = 30;
            }
            return correctHour + ':' + correctMin;

        }

拿你代码做了一点修改