Class YAHOO.util.Connect

Object
   |
   +--YAHOO.util.Connect

class YAHOO.util.Connect

Field Summary [top]

boolean _has_http_headers
Determines if HTTP headers are set. 
object _http_header
Object of HTTP header(s) 
boolean _default_post_header
Determines if a default header of Content-Type of 'application/x-www-form-urlencoded' will be added to any client HTTP headers for POST transactions.
object _formNode
Property modified by setForm() to set a reference to the HTML form node if the desired action is file upload.;
boolean _isFileUpload
Property modified by setForm() to set the HTML form data for each transaction. 
boolean _isFormSubmit
Property modified by setForm() to determine if the data should be submitted as an HTML form. 
array _msxml_progid
Array of MSFT ActiveX ids for XMLHttpRequest. 
array _poll
Collection of polling references to the polling mechanism in handleReadyState. 
int _polling_interval
The polling frequency, in milliseconds, for HandleReadyState. 
string _sFormData
Property modified by setForm() to set the HTML form data for each transaction. 
array _timeOut
Queue of timeout values for each transaction callback with a defined timeout value. 
int _transaction_id
A transaction counter that increments the transaction id for each transaction. 

Method Summary [top]

Object abort (<object> o)
Public method to terminate a transaction, if it has not reached readyState 4. 
object asyncRequest (<string> method, <string> uri, callback, <string> postData)
Method for initiating an asynchronous request via the XHR object. 
Object createExceptionObject (<int> tId, <object> callbackArg)
If a transaction cannot be completed due to dropped or closed connections, there may be not be enough information to build a full response object. 
Object createResponseObject (<object> o, <object> callbackArg)
This method evaluates the server response, creates and returns the results via its properties. 
Object createXhrObject (<int> transactionId)
Instantiates a XMLHttpRequest object and returns an object with two properties: the XMLHttpRequest instance and the transaction id. 
Object getConnectionObject ()
This method is called by asyncRequest to create a valid connection object for the transaction. 
Object handleReadyState (<object> o, callback)
This method serves as a timer that polls the XHR object's readyState property during a transaction, instead of binding a callback to the onreadystatechange event. 
Object handleTransactionResponse (<object> o, <function> callback)
This method attempts to interpret the server response and determine whether the transaction was successful, or if an error or exception was encountered. 
Object initHeader (<string> label,<string> value)
Public method that stores the custom HTTP headers for each transaction. 
Object isCallInProgress (<object> o)
Public method to check if the transaction is still being processed. 
Object releaseObject (<object> o)
Dereference the XHR instance and the connection object after the transaction is completed. 
Object setDefaultPostHeader (<boolean> b)
Member to enable or disable the default POST header. 
Object setForm (formId)
This method assembles the form label and value pairs and constructs an encoded string. 
Object setHeader (<object> o)
Accessor that sets the HTTP headers for each transaction. 
Object setPollingInterval (<int> i)
Member to modify the default polling interval. 
Object setProgId (id)
Member to add an ActiveX id to the existing xml_progid array. 

Field Detail [top]

_has_http_headers

boolean   _has_http_headers
Determines if HTTP headers are set.

_http_header

object   _http_header
Object of HTTP header(s)

_isFormSubmit

boolean   _isFormSubmit
Property modified by setForm() to determine if the data should be submitted as an HTML form.

_msxml_progid

array   _msxml_progid
Array of MSFT ActiveX ids for XMLHttpRequest.

_poll

array   _poll
Collection of polling references to the polling mechanism in handleReadyState.

_polling_interval

int   _polling_interval
The polling frequency, in milliseconds, for HandleReadyState. when attempting to determine a transaction's XHR readyState. The default is 50 milliseconds.

_sFormData

string   _sFormData
Property modified by setForm() to set the HTML form data for each transaction.

_transaction_id

int   _transaction_id
A transaction counter that increments the transaction id for each transaction.

Method Detail [top]

abort

Object abort (<object> o)
Public method to terminate a transaction, if it has not reached readyState 4.
Parameters:
o - The connection object returned by asyncRequest.
Returns:
void

asyncRequest

object asyncRequest (<string> method, <string> uri, <object> callback, <string> postData)
Method for initiating an asynchronous request via the XHR object.
Parameters:
method - HTTP transaction method
uri - Fully qualified path of resource
callback - User-defined callback function or object
postData - POST body
Returns:
Returns the connection object

createExceptionObject

Object createExceptionObject (<int> tId, <object> callbackArg)
If a transaction cannot be completed due to dropped or closed connections, there may be not be enough information to build a full response object. The failure callback will be fired and this specific condition can be identified by a status property value of 0.
Parameters:
tId - Transaction Id
callbackArg - User-defined argument or arguments to be passed to the callback.
Returns:
object

createResponseObject

Object createResponseObject (<object> o, <object> callbackArg)
This method evaluates the server response, creates and returns the results via its properties. Success and failure cases will differ in the response object's property values.
Parameters:
o - The connection object
callbackArg - User-defined argument or arguments to be passed to the callback
Returns:
object

createXhrObject

Object createXhrObject (<int> transactionId)
Instantiates a XMLHttpRequest object and returns an object with two properties: the XMLHttpRequest instance and the transaction id.
Parameters:
transactionId - Property containing the transaction id for this transaction.
Returns:
connection object

getConnectionObject

Object getConnectionObject ()
This method is called by asyncRequest to create a valid connection object for the transaction. It also passes a transaction id and increments the transaction id counter.
Returns:
object

handleReadyState

Object handleReadyState (<object> o, <object> callback)
This method serves as a timer that polls the XHR object's readyState property during a transaction, instead of binding a callback to the onreadystatechange event. Upon readyState 4, handleTransactionResponse will process the response, and the timer will be cleared.
Parameters:
o - The connection object
callback - User-defined callback object
Returns:
void

handleTransactionResponse

Object handleTransactionResponse (<object> o, <function> callback)
This method attempts to interpret the server response and determine whether the transaction was successful, or if an error or exception was encountered.
Parameters:
o - The connection object
callback - - User-defined callback object
Returns:
void

initHeader

Object initHeader (<string> label,<string> value)
Public method that stores the custom HTTP headers for each transaction.
Parameters:
label - The HTTP header label
value - The HTTP header value
Returns:
void

isCallInProgress

Object isCallInProgress (<object> o)
Public method to check if the transaction is still being processed.
Parameters:
o - The connection object returned by asyncRequest
Returns:
boolean

releaseObject

Object releaseObject (<object> o)
Dereference the XHR instance and the connection object after the transaction is completed.
Parameters:
o - The connection object
Returns:
void

setForm

Object setForm (formId)
This method assembles the form label and value pairs and constructs an encoded string. asyncRequest() will automatically initialize the transaction with a HTTP header Content-Type of application/x-www-form-urlencoded.
Parameters:
string - || object} form id or name attribute, or form object.
Returns:
void

setHeader

Object setHeader (<object> o)
Accessor that sets the HTTP headers for each transaction.
Parameters:
o - The connection object for the transaction.
Returns:
void

setPollingInterval

Object setPollingInterval (<int> i)
Member to modify the default polling interval.
Parameters:
i - The polling interval in milliseconds.
Returns:
void

setProgId

Object setProgId (id)
Member to add an ActiveX id to the existing xml_progid array. In the event a new ActiveX id is introduced, it can be added without internal code modifications.
Parameters:
string - id The ActiveX id to be added to initialize the XHR object.
Returns:
void