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JavaScript indexOf() Method
Example
Search an array for the item "Apple":
var fruits = ["Banana", "Orange", "Apple", "Mango"];
var a = fruits.indexOf("Apple");
var a = fruits.indexOf("Apple");
The result of a will be:
2
Meaning that "Apple" is located at position 2 in the array.
Try it yourself »Definition and Usage
The indexOf() method searches the array for the specified item, and returns its position.
The search will start at the specified position, or at the beginning if no start position is specified, and end the search at the end of the array.
Returns -1 if the item is not found.
If the item is present more than once, the indexOf method returns the position of the first occurence.
Note: The first item has position 0, the second item has position 1, and so on.
Tip: If you want to search from end to start, use the lastIndexOf() method
Browser Support
The indexOf() method is not supported in Internet Explorer 8 and earlier.
Syntax
array.indexOf(item,start)
Parameter Values
| Parameter | Description |
|---|---|
| item | Required. The item to search for |
| start | Optional. Where to start the search. Negative values will start at the given position counting from the end, and search to the end. |
Return Value
| Type | Description |
|---|---|
| Number | The position of the specified item, otherwise -1 |
Technical Details
| JavaScript Version: | 1.6 |
|---|
More Examples
Example
Search an array for the item "Apple", starting the search at position 4:
var fruits=["Banana","Orange","Apple","Mango","Banana","Orange","Apple"];
var a = fruits.indexOf("Apple",4);
var a = fruits.indexOf("Apple",4);
The result of a will be:
6
Try it yourself »
JavaScript Array Object
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