JavaScript: Maximum date from an array of dates

JavaScript Datetime: Exercise-11 with Solution

Max Date in Array

Write a JavaScript function to get the maximum date from an array of dates.

Test Data:
console.log(max_date(['2015/02/01', '2015/02/02', '2015/01/03']));
Output :
"2015/02/02"

Sample Solution:

JavaScript Code:

// Define a JavaScript function called max_date with parameter all_dates
function max_date(all_dates) {
  // Initialize variables to store the maximum date and its corresponding Date object
  var max_dt = all_dates[0],
      max_dtObj = new Date(all_dates[0]);

  // Iterate through each date in the array using forEach method
  all_dates.forEach(function(dt, index) {
    // Convert the current date string to a Date object
    var current_dtObj = new Date(dt);

    // Compare the current Date object with the maximum Date object
    if (current_dtObj > max_dtObj) {
      // If the current Date object is greater than the maximum Date object, update the maximum date
      max_dt = dt;
      max_dtObj = new Date(dt);
    }
  });

  // Return the maximum date
  return max_dt;
}

// Output the maximum date from the provided array of dates
console.log(max_date(['2015/02/01', '2015/02/02', '2015/01/03']));

Output:

2015/02/02

Explanation:

In the exercise above,

• The code defines a JavaScript function named "max_date()" with one parameter 'all_dates', representing an array of date strings.
• Inside the function:
• It initializes two variables: 'max_dt' to store the maximum date string found so far and 'max_dtObj' to store the corresponding Date object of the maximum date.
• It converts the first date string in the 'all_dates' array to a Date object and assigns it to 'max_dtObj'.
• It iterates through each date string in the 'all_dates' array using the "forEach()" method.
• Inside the loop:
• It converts the current date string to a Date object.
• It compares the current Date object with the maximum Date object (max_dtObj).
• If the current Date object is greater than 'max_dtObj', it updates 'max_dt' and 'max_dtObj' to the current date string and Date object, respectively.
• After iterating through all date strings, it returns the maximum date ('max_dt').
• The code then demonstrates the usage of the "max_date()" function by calling it with an array of date strings ['2015/02/01', '2015/02/02', '2015/01/03'].

Flowchart:

Live Demo:

See the Pen JavaScript - Maximum date from an array of dates-date-ex- 11 by w3resource (@w3resource) on CodePen.

Improve this sample solution and post your code through Disqus.

Previous: Write a JavaScript function to calculate 'yesterday day'.
Next: Write a JavaScript function to get the minimum date from an array of dates.