# array.isDefined()

Returns whether there exists an item in the array at the selected index.

```
array.isDefined( index=number )
```

**Returns:** boolean

# Arguments

| Argument | Type | Required | Description | Default |
|----------|------|----------|-------------|---------|
| index | number | Yes | The index which to check |  |

# Examples

```cfml
water = ["sea","river","well","bottle"];
writeDump(water.isdefined(0));
writeDump(water.isdefined(5));
writeDump(water.isdefined(4));
```

# Categories

[Arrays](../../../categories/array.md), [Decision logic](../../../categories/decision.md)

# See Also

[ArrayIsDefined()](../../functions/arrayisdefined.md), [Array](../array.md)