typescript - 从日期中获取日期名称

Question

I tried to get the day name from a date, but with the date 27/02/2021 i get Invalid Date

new Date(exam.examDate).toLocaleString('fr-FR', { weekday: 'long' })

i tried to convert the date using datePipe but it return the below error

Unable to convert "27/02/2021" into a date' for pipe 'DatePipe

new Date(this.datePipe.transform(exam.examDate, "dd/MM/yyyy")).toLocaleString('fr-FR', { weekday: 'long' })

Answer 1

You can get a custom day name from Date like:

const names = ['Sunday', 'Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday', 'Saturday'];
const dayName = names[dateObject.getDay()];

 const date = '27/02/2021'; const d = date.split('/'); const names = ['Sunday', 'Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday', 'Saturday']; const dayName = names[new Date(d[2],d[1],d[0]).getDay()]; console.log(dayName);

Answer 2

This is because Date expects MM/DD/YYYY but you're passing DD/MM/YYYY :

 const getDay = date => { const parts = date.split('/'); return new Date(+parts[2], +parts[1] - 1, +parts[0]).toString().split(' ')[0]; } console.log( getDay('27/02/2021') );

Using moment.js :

 const getDay = date => moment(date, "DD/MM/YYYY").format('ddd'); console.log( getDay('27/02/2021') );

 <script src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.29.1/moment.min.js" integrity="sha512-qTXRIMyZIFb8iQcfjXWCO8+M5Tbc38Qi5WzdPOYZHIlZpzBHG3L3by84BBBOiRGiEb7KKtAOAs5qYdUiZiQNNQ==" crossorigin="anonymous"></script>

Answer 3

 examDate = "27/02/2021"; date = examDate.split("/"); x = new Date(date[2], date[1] - 1, date[0]); // it prints "samedi" console.log(x.toLocaleString('fr-FR', { weekday: 'long' }));