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.. » JavaScript » Loops » For...In Loops
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For...In Loops

The JavaScript For...In loop specifically allows you to loop through all the values of an array or object. The syntax is,
 for (index in array/object){
//Do anything with values
}
Where the index is just any variable name e.g "x" representing and holding the index number(array) or named index(object) any time it executes while the array/object is any array or object to loop through. Using the for...in loop is the easiest way to access an array or object but then, it must access all values unlike the for or while loop which can access a specified part of an array. Loop Arrays
<script>
var arr = ["Stack","Beginner","Tutorial"]; //An array

for (i in arr){
alert(arr[i]);
}
</script>

Copy PRACTICE IT

Loop Objects
<script>
var obj = {name: "Omamode", age:23, isAdult:true}; //object

for (name_index in obj){
alert(obj[name_index])
}
</script>

Copy PRACTICE IT

SUMMARY
  1. The JavaScript for...in loop specifically allows us loop through all the values of an array or object.
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