url_encode requirements
================

## Overview

This document will specify the requirements for URL_Encode.

## Exposed API

```c
extern STRING* URL_Encode(STRING* input);
```

### URL_Encode

URL_Encode will take as a parameter a pointer to a STRING, input.  URL_Encode will return a pointer to STRING.
**SRS_URL_ENCODE_06_001: [** If input is NULL then URL_Encode will return NULL. **]**

**SRS_URL_ENCODE_06_002: [** If an error occurs during the encoding of input then URL_Encode will return NULL. **]**

**SRS_URL_ENCODE_06_003: [** If input is a zero length string then URL_Encode will return a zero length string. **]**
URL_Encode will encode input in a manner that respects the encoding used in the .net HttpUtility.UrlEncode.