How to compare two arrays in JavaScript?

In Javascript, to compare two arrays we need to check that the length of both arrays should be same, the objects present in it are of the same type and each item in one array is equal to the counterpart in another array. By doing this we can conclude both arrays are the same or not. JavaScript provides a function JSON.stringify() in order to convert an object or array into JSON string. By converting into JSON string we can directly check if the strings are equal or not.

Example #1:

<script> 
var a = [1, 2, 3, 5]; 
var b = [1, 2, 3, 5]; 
// comparing both arrays using stringify 
if(JSON.stringify(a)==JSON.stringify(b)) 
 document.write("True"); 
else
 document.write("False"); 
 document.write('<br>'); 
var f=[1, 2, 4, 5]; 
if(JSON.stringify(a)==JSON.stringify(f)) 
 document.write("True"); 
else
 document.write("False"); 
</script> 

Output:

True
False

Example #2:
In this example we manually checking each and every item and return True if they are equal otherwise return False.

<script> 
function isEqual() 
{ 
 var a = [1, 2, 3, 5]; 
 var b = [1, 2, 3, 5]; 
  // if length is not equal 
  if(a.length!=b.length) 
   return "False"; 
  else
  { 
  // comapring each element of array 
   for(var i=0;i<a.length;i++) 
   if(a[i]!=b[i]) 
    return "False"; 
    return "True"; 
  } 
} 
var v = isEqual(); 
document.write(v); 
</script> 

Output:

True

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