Question

我试图借助JS瞬间创建一个自定义的日期选择器。当年份改变时，我无法获得正确月份的日期的问题

getDaysArrayByMonth()仅返回2018年的月份

  public selectedMonth: any
  private monthIterator = 0
  public daysOfSelectedMonth = [];
  public monthDaysAmount: number

  onNextMonth() {
    this.monthIterator++
    this.selectedMonth = moment().add(this.monthIterator, 'months').format('MMMM YYYY');
    this.getDaysArrayByMonth()
  }

  onPreviousMonth() {
    this.monthIterator--
    this.selectedMonth = moment().add(this.monthIterator, 'months').format('MMMM YYYY');
    this.getDaysArrayByMonth()

  }

  getDaysArrayByMonth(){
    this.daysOfSelectedMonth = []
    this.monthDaysAmount = moment().month(this.selectedMonth).daysInMonth() ;
    const remainingToEvenRows = 35 - this.monthDaysAmount
    const days = this.monthDaysAmount + remainingToEvenRows

    for (let i = 0; i < days; i++) {
      this.daysOfSelectedMonth.push(moment().month(this.selectedMonth).date(i + 1).format('Do MMMM YYYY'));
    }
  }

Answer 1

this.selectedMonth将保存月份和年份，因此您应该在瞬间构造函数中使用结果：

moment(this.selectedMonth, 'MMMM YYYY')

this.monthDaysAmount = moment(this.selectedMonth, 'MMMM YYYY').daysInMonth() ;
for (let i = 0; i < days; i++) {
  this.daysOfSelectedMonth.push(moment(this.selectedMonth, 'MMMM YYYY').date(i + 1).format('Do MMMM YYYY'));
}

Answer 2

moment()函数始终返回当前日期，因此，如果您要在其上构建逻辑，它将始终返回当前月份和年份。因此您必须在构造函数中指定年份和月份，以返回所需/过去的月份。

因此，请按以下方式更改此代码

/// public selectedMonth: any
private monthIterator = 0
public daysOfSelectedMonth = [];
public monthDaysAmount: number

onNextMonth() {
this.monthIterator++
/// this.selectedMonth = moment().add(this.monthIterator, 'months').format('MMMM YYYY');
this.getDaysArrayByMonth(moment("201501", "YYYYMM").add(1, 'months').format('YYYYMM'));
}

onPreviousMonth() {
this.monthIterator--
/// this.selectedMonth = moment().add(this.monthIterator, 'months').format('MMMM YYYY');

this.getDaysArrayByMonth(moment("201501", "YYYYMM").add(1, 'months').format('YYYYMM'))
}

getDaysArrayByMonth(yearMonth: string){
this.daysOfSelectedMonth = []
/// this.monthDaysAmount = moment().month(this.selectedMonth).daysInMonth() ;
this.monthDaysAmount = moment(yearMonth,'YYYYMM').daysInMonth() ;
const remainingToEvenRows = 35 - this.monthDaysAmount
const days = this.monthDaysAmount + remainingToEvenRows

for (let i = 0; i < days; i++) {
  this.daysOfSelectedMonth.push(moment().month(this.selectedMonth).date(i + 1).format('Do MMMM YYYY'));
}

}

请删除硬编码的201501，并将YearMonth组合传递给函数onNextMonth和onPreviousMonth。

选中此stackblitz

使用JS和Angular时刻获取特定年份的月份中的几天

2 个答案: