## Include headers
### AutoConnect.h
```cpp
#include
```
#### Define macros
```cpp
#define AC_DEBUG // Monitor message output activation
#define AC_DEBUG_PORT Serial // Default message output device
#define AUTOCONNECT_AP_IP 0x01F4A8C0 // Default SoftAP IP
#define AUTOCONNECT_AP_GW 0x01F4A8C0 // Default SoftAP Gateway IP
#define AUTOCONNECT_AP_NM 0x00FFFFFF // Default subnet mask
#define AUTOCONNECT_DNSPORT 53 // Default DNS port at captive portal
#define AUTOCONNECT_HTTPPORT 80 // Default HTTP
#define AUTOCONNECT_MENU_TITLE "AutoConnect" // Default AutoConnect menu title
#define AUTOCONNECT_STARTUPTIME 10 // Default waiting time[s] for after reset
#define AUTOCONNECT_URI "/_ac" // Default AutoConnect root path
#define AUTOCONNECT_TIMEOUT 30000 // Default connection timeout[ms]
```
## AutoConnect API
### Constructors
#### AutoConnect
```cpp
AutoConnect()
```
AutoConnect default constructor. This entry activates WebServer internally and the web server is allocated internal.
```cpp
AutoConnect(ESP8266WebServer& webServer)
```
Run the AutoConnect site using the externally ensured ESP 8266 WebServer. User's added URI handler response can be included in handleClient method.
- **Parameters**
- webServerA reference of ESP8266WebServer instance.
### Public member functions
#### begin
```cpp
bool begin()
```
```cpp
bool begin(const char* ssid, const char* passphraase)
```
```cpp
bool begin(const char* ssid, const char* passphraase, unsinged long timeout)
```
Starts establishing WiFi connection. Before establishing, start the Web server and DNS server for the captive portal. Then begins connection establishment in WIFI_STA mode. If connection can not established with the specified SSID and password, switch to WIFI_AP_STA mode and activate SoftAP.
- **Parameters**
- ssidSSID to be connected.
- passphrasePassword for connection.
- timeoutA time out value in milliseconds for waiting connection.
- **Return value**
- trueConnection established, AutoConnect service started with WIFI_STA mode.
- falseCould not connected, Captive portal started with WIFI_AP_STA mode.
#### config
```cpp
bool config(AutoConnectConfig& config)
```
```cpp
bool config(const char* ap, const char* password = nullptr)
```
Sets SoftAP's WiFi configuration.
- **Parameters**
- configReference to AutoConnectConfig containing SoftAP's parameters.
- apSSID for SoftAP. The default value is **esp8266ap**.
- passwordPassword for SodtAP. The default value is **12345678**.
- **Return value**
- trueSuccessfully configured.
- falseConfiguration parameter is invalid, some values out of range.
#### end
```cpp
void end()
```
Stops AutoConnect captive portal service. Release ESP8266WebServer and DNSServer.
!!! warning "Attention to end"
The end function releases the instance of ESP8266WebServer and DNSServer. It can not process them after the end function.
#### handleClient
```cpp
void handleClient()
```
Handling for the AutoConnect web interface. Invoke the handleClient of the parent web server to process client request of the AutoConnect WEB interface. No effects when the web server is not available.
#### handleRequest
```cpp
void handleRequest()
```
Handling for the AutoConnect menu request.
!!! warning "About used in combination with handleClient"
The handleRequest function is not supposed to use with AutoConnect::handleClient. It should be used with ESP8266::handleClient.
#### home
```cpp
void home(String uri)
```
Put a user site's home URI. The URI specified by home is linked from "HOME" in the AutoConnect portal menu.
- **Parameters**
- uri A URI string of user site's home path.
#### host
Returns the reference of the ESP8266WebServer which is allocated in AutoConnect automatically.
```cpp
ESP8266WebServer& host()
```
- **Return value**
- A reference of the ESP8266WebServer.
!!! note "&reference is not a pointer"
A reference cannot be re-assigned, and must be assigned at initialization. It's like as bind as alias.
```cpp
ESP8266WebServer& server = portal.host();
server.handleClient();
```
or
```cpp
portal.host().handleClient();
```
#### onDetect
```cpp
void onDetect(DetectExit_ft fn)
```
Register the function which will call from AutoConnect at the start of the captive portal.
- **Parameters**
- fnFunction called at the captive portal start.
An *fn* specifies the function called when the captive portal starts. Its prototype declaration is defined as "*DetectFunc_ft*".
```cpp
typedef std::function DetectExit_ft
```
- **Parameters**
- softapIPAn IP address of SoftAP for the captive portal.
- **Retuen value**
- trueContinues captive portal handling.
- falseCancel the captive portal. AutoConnect::begin function will return with a false.
#### onNotFound
```cpp
void onNotFound(ESP8266WebServer::THandlerFunction fn)
```
Register the handler function for undefined URL request detected.
- **Parameters**
- fnA function of the "not found" handler.
## AutoConnectConfig API
### Constructor
#### AutoConnectConfig
```cpp
AutoConnectConfig();
```
```cpp
AutoConnectConfig(const char* ap, const char* password);
```
- **Parameters**
- apSSID for SoftAP. The length should be up to 31. The default value is **esp8266ap**.
- passwordPassword for SodtAP. The length should be from 8 to up to 63. The default value is **12345678**.
### Public member variables
#### apid
SoftAP's SSID.
- **Type**
- String
#### apip
Sets IP address for Soft AP in captive portal. When AutoConnect fails the initial WiFi.begin, it starts the captive portal with the IP address specified this.
- **Type**
- IPAddress
#### autoReset
Reset ESP8266 module automatically when WLAN disconnected.
- **Type**
- bool
- **Value**
- trueReset after WiFi disconnected automatically.
- falseNo reset.
#### autoRise
Captive portal activation switch. False for disabling the captive portal. It prevents starting the captive portal even if the connection at the first *WiFi.begin* fails.
- **Type**
- bool
- **Value**
- trueEnable the captive portal. This is a default.
- falseDisable the captive portal.
#### autoSave
The credential saved automatically at the connection establishment.
- **Type**
- AC_SAVECREDENTIAL_t
- **Value**
- AC_SAVECREDENTIAL_AUTOThe credential saved automatically.
- AC_SAVECREDENTIAL_NEVERThe credential no saved.
#### channel
The channel number of WIFi when SoftAP starts.
- **Type**
- uint8_t
- **Value**
- 1 ~ 14. The default value is 1.
!!! info "See Application note"
Espressif Systems had announced the [application note](https://www.espressif.com/sites/default/files/esp8266_wi-fi_channel_selection_guidelines.pdf) about Wi-Fi channel selection.
#### gateway
Sets gateway address for Soft AP in captive portal. When AutoConnect fails the initial WiFi.begin, it starts the captive portal with the IP address specified this.
- **Type**
- IPAddress
#### hidden
Sets SoftAP to hidden SSID.
- **Type**
- uint8_t
- **Value**
- 0SSID will be appeared. This is the default.
- 1SSID will be hidden.
#### homeUri
Sets the home path of user sketch. This path would be linked from 'HOME' in the AutoConnect menu.
- **Type**
- String
#### netmask
Sets subnet mask for Soft AP in captive portal. When AutoConnect fails the initial WiFi.begin, it starts the captive portal with the IP address specified this.
- **Type**
- IPAddress
#### psk
Sets password for SoftAP. The length should be from 8 to up to 63. The default value is **12345678**.
- **Type**
- String
#### saveOffset
Sets the offset address of the credential storage area for EEPROM. This value must be between greater than 4 and less than flash sector size. (4096 by SDK)
The default value is 0.
- **Type**
- uint16_t
!!! warning "It will conflict with user data."
If the sketch leaves this offset at zero, it will conflict the storage area of credentials with the user sketch owned data. It needs to use the behind of credential area.
### AutoConnectConfig example
```arduino
AutoConenct Portal;
AutoConenctConfig Config("", "passpass"); // SoftAp name is determined at runtime
Config.apid = ESP.hostname(); // Retrieve host name to SotAp identification
Config.apip = IPAddress(192,168,10,101); // Sets SoftAP IP address
Config.gateway = IPAddress(192,168,10,1); // Sets WLAN router IP address
Config.netmask = IPAddress(255,255,255,0); // Sets WLAN scope
Config.autoSave = AC_SAVECREDENTIAL_NEVER; // No save credential
Config.homeUri = "/index.html" // Sets home path of the sketch application
Portal.config(Config); // Configure AutoConnect
Portal.begin(); // Starts and behaves captive portal
```
## Something extra
The library presents two PNG icons which can be used to embed a hyperlink to the AutoConnect menu.
- Bar type 
- Cog type 
To reference the icon, use the **AUTOCONNECT_LINK** macro in the sketch. It expands into the string literal as an HTML `````` tag with PNG embedded of the AutoConnect menu hyperlinks. Icon type is specified by the parameter of the macro.
- BAR_32Bars icon, 32x32.
- BAR_48Bars icon, 48x48.
- COG_24Cog icon, 24x24.
- COG_32Cog icon, 32x32.
!!! note "Usage"
```arduino
String html = "";
html += AUTOCONNECT_LINK(BAR_32);
html += "";
server.send(200, "text/html", html);
```