Hello everyone. Can you help me with this kind of question? I want to encrease days in date string, so code is kind like this.

var date = new Date()
date.setDate(date.getDate()   1)

The problem is that i want to change only days without month, years or time (h m s). So, for example if i have date 31 december 2021 and i encrease day by one i want to get 01 december 2021 and not 01 january 2022. Is it possible in JS?

CodePudding user response：

You'll just have to manually check and adjust if needed. Here's an example function:

var date = new Date('12/31/2021');

incremenetLoopingDate(date);
console.log(date);

function incremenetLoopingDate(date){
  var mo = date.getMonth();
  date.setDate(date.getDate()   1);
  if(date.getMonth() !== mo){
    date.setMonth(mo);
  }
  return date;
}

<iframe name="sif1" sandbox="allow-forms allow-modals allow-scripts" frameborder="0"></iframe>

CodePudding user response：

Similar to the other answer, but simpler. Just check if the incremented date is 1 and if so, set to the previous month. Note that this modifies the passed date.

function incrementMonthLoop(date = new Date()) {
  date.setDate(date.getDate()   1);
  if (date.getDate() == 1) date.setMonth(date.getMonth() - 1);
  return date;
}

console.log(
  incrementMonthLoop(new Date(2021, 11, 31)).toDateString()
);

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