# IsLocalHost

Determine whether a given string value represents a loopback IP address, like `localhost`, `127.0.0.1` or `::1`.

## Method Signature

```
IsLocalHost(ip=[string])
```

### Arguments

| Argument | Type     | Required | Description                                 | Default |
| -------- | -------- | -------- | ------------------------------------------- | ------- |
| `ip`     | `string` | `true`   | String representing the IP address to test. |         |

## Examples

### Is 127.0.0.1 localhost

[Run Example](https://try.boxlang.io/?code=eJzLLPbJT07M8cgvLtFQUDI0MtczAEJDJQVNay4AfssHNQ%3D%3D)

```java
isLocalHost( "127.0.0.1" );

```

Result: true

### Is ::1 localhost

Test the IPv6 Loopback address. IPv6 only has one loopback address.

[Run Example](https://try.boxlang.io/?code=eJzLLPbJT07M8cgvLtFQULKyMlRS0LTmAgBVSwYl)

```java
isLocalHost( "::1" );

```

Result: true

### Is 127.8.8.8 localhost

IPv4 network standards reserve the entire 127.0.0.0/8 address block for loopback networking purposes however they are not usually mapped to `localhost` by default.

[Run Example](https://try.boxlang.io/?code=eJzLLPbJT07M8cgvLtFQUDI0MtezAEElBU1rLgB%2FhQdM)

```java
isLocalHost( "127.8.8.8" );

```

Result: true

### Is 8.8.8.8 localhost

Not a localhost IP.

[Run Example](https://try.boxlang.io/?code=eJzLLPbJT07M8cgvLtFQULLQA0MlBU1rLgBwuQbq)

```java
isLocalHost( "8.8.8.8" );

```

Result: false

### Additional Examples

```java
ip = "127.0.0.1";
writeDump( islocalhost( ip ) ); // true
writeDump( islocalhost( GetLocalHostIP() ) );
 // true

```

## Related

* [ArrayIsEmpty](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/arrayisempty)
* [arrayIsEmpty](https://github.com/ortus-boxlang/boxlang-docs/blob/v1.x/boxlang-language/reference/built-in-functions/decision/arrayIsEmpty.md)
* [Attempt](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/attempt)
* [IsArray](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isarray)
* [IsBinary](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isbinary)
* [IsBoolean](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isboolean)
* [IsClosure](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isclosure)
* [IsCustomFunction](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/iscustomfunction)
* [IsDate](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isdate)
* [IsDateObject](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isdateobject)
* [IsDebugMode](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isdebugmode)
* [IsDefined](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isdefined)
* [IsEmpty](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isempty)
* [IsFileObject](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isfileobject)
* [IsIPv6](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isipv6)
* [IsJSON](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isjson)
* [IsLeapYear](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isleapyear)
* [IsNull](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isnull)
* [IsNumeric](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isnumeric)
* [IsNumericDate](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isnumericdate)
* [IsObject](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isobject)
* [IsQuery](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isquery)
* [IsSimpleValue](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/issimplevalue)
* [IsStruct](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isstruct)
* [IsValid](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isvalid)
* [IsXML](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isxml)
* [IsXmlAttribute](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isxmlattribute)
* [IsXMLDoc](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isxmldoc)
* [IsXMLElem](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isxmlelem)
* [IsXMLNode](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isxmlnode)
* [IsXMLRoot](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isxmlroot)
* [LSIsNumeric](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/lsisnumeric)
* [structIsEmpty](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/structisempty)


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