JavaScript object instance

JavaScript object instance

Use the built-in JavaScript object instance.

String object

• Returns the length of the string
• Add a style to the string
• Returns the location in the string where the text first appears - the indexOf() method
• Finds a specific character in the string and, if found, returns the character - the match() method
• Replace characters in string - replace()


• More examples of string objects in our JavaScript String object reference manual.

Date object

• Use the Date() method to return today's date and time
• Use getTime() to calculate how many milliseconds there are from 1970 to today
• Use setFullYear() to set a specific date
• Use toUTCString() to convert the date of the day (according to UTC) to a string
• Use getDay() to display the week, not just the numbers
• Show a clock


• More examples of Date objects in our JavaScript Date object reference manual.

Array object

• Create an array
• Merge two arrays - concat()
• Merge three arrays - concat()
• Strings made up of elements of an array - join()
• Remove the last element of the array - pop()
• Add a new element at the end of the array - push()
• Reverse the order of elements in an array - reverse()
• Remove the first element of the array - shift()
• Select elements from an array - slice()
• Array sorting (ascending in alphabetical order) - sort ()
• Number sorting (ascending in numerical order) - sort ()
• Number sorting (descending in numerical order) - sort ()
• Add an element at the 2nd position of the array - splice()
• Convert array to string -toString()
• Add a new element at the beginning of the array - unshift()


• More examples of Array objects in our JavaScript Array object reference manual.

Boolean (Boolean) object

• Check the logical values


• More examples of Boolean object objects in our JavaScript Boolean object reference manual.

Math object

• Round the numbers using round().
• Use random() to return a random number between 0 and 1
• Use max() to return a larger number of two given numbers
• Use min() to return a smaller number of two given numbers
• Celsius and Fahrenheit conversion

So so

• Use for... through object elements The in statement


• More Math object examples in our JavaScript Math object reference manual.