Ajaxpro usage, learn about background code for JS synchronous and asynchronous calls

I. ajaxpro usage 1. add a reference to the project and navigate to the ajaxpro.2.dll file. Note: Download ajaxpro.2.dll online. 2. in the web. system. write the following code into the web: <configuration>
<System. Web>
<Httphandlers>
<Add verb = "*" Path = "*. ashx" type = "ajaxpro. ajaxhandlerfactory, ajaxpro.2"/>
</Httphandlers>
</System. Web>
</Configuration> 3. Add
Ajaxpro. utility. registertypeforajax (typeof (Class Name); 4. the background method should use [ajaxpro. ajaxmethod. the name of the namespace must be clearly written during the call. class Name. method, for example:
Ajaxtest. _ default. getdata ();

6. The call can be divided into two methods (synchronous call and asynchronous call)

// No parameter method written in the background
[Ajaxpro. ajaxmethod]
Public String getstr ()
{
Return "Hello my friends ";
}
// The method with parameters written in the background
[Ajaxpro. ajaxmethod]
Public String getstring (string Str)
{
Return STR + "say: Hello my friends ";
}

 

A. synchronous call
(1) drag the HTML control button
(2) double-click to automatically display it in the. aspx script.
(3). Write the content you want to enter in it
Example: // ------------------ synchronous call without parameter -----------
Function button1_onclick ()
{
VaR res = webui. _ default. getstr ();
Alert (res. value );
}

// ------------------ Synchronous call with parameter ------------
Function button2 _ // textbox1 is the Server Control
{
VaR STR = Document. getelementbyid ("<% = textbox1.clientid %>"). value;
VaR res = webui. _ default. getstr (STR );
Alert (res. value );
}

B. asynchronous call
(1) drag the HTML control button
(2) double-click to automatically display it in the. aspx script.
(3). Write the content you want to enter in it
For example: // ----------------- The asynchronous call has no parameter -----------------
Function button3 _{
Webui. _ default. getstr (getstrcallback );
}
Function getstrcallback (RES)
{
Alert (res. value );
}
// ----------------- Asynchronous call with parameter -----------------
Function button4 _{
VaR STR = Document. getelementbyid ("<% = textbox1.clientid %>"). value;
Webui. _ default. getstring (STR, getstringcallback );
}
Function getstringcallback (RES)
{
Alert (res. value );
}

Note: During asynchronous calling, the background method cannot be reloaded; otherwise, an error occurs.

2. Direct call
Javascript: <% = background method %>

Function says ()
{
Alert ("<% = say () %> ");
}
Function del ()
{
Alert ("<% = deletebyid (8) %>"); // ebyid (8) Background method name
}

Iii. Adopt icallbackeventhandler callback

/**//*
* To declare the icallbackeventhandler interface, you must declare the interface and implement it by calling the server code on the client without sending it back:
* Raisecallbackevent () and getcallbackresult ()
* The raisecallbackevent () parameter is transmitted from the foreground. Different codes are executed based on the transmitted parameters and the result is returned to the foreground using getcallbackresult ().
*/

// The system. Web. UI. icallbackeventhandler interface must be declared.
Public partial class _ default: system. Web. UI. Page, system. Web. UI. icallbackeventhandler
{
// Define the return value of a callback
Private string result;
// Define two variables to receive page-passed operands
Private string num1;
Private string num2;
Protected void page_load (Object sender, eventargs E)
{

}
/// <Summary>
/// This method is the method for callback execution. The callback content is processed according to parameters in this method, and no return value is returned for this method.
/// </Summary>
/// <Param name = "eventargument"> this parameter is transmitted from the client. </param>

Public void raisecallbackevent (string eventargument)
{
// Eventargumeng is the parameter passed by JavaScript from the client. In this example, the three parameters are separated by "/" and each parameter is retrieved and saved to an array.
String [] pagparams = eventargument. Split ('/');
Num1 = pagparams [1];
Num2 = pagparams [2];
// Call different execution functions based on the first parameter (selected operator)
Switch (pagparams [0])
{
Case "0 ":
Result = add (); break;
Case "1 ":
Result = sub (); break;
Case "2 ":
Result = multi (); break;
Case "3 ":
Result = Division (); break;
}
}

/** // <Summary>
/// This method returns the callback result to the client.
/// </Summary>
/// <Returns> </returns>
Public String getcallbackresult ()
{
Return result;
}

// The following four functions use the raisecallbackevent method. The called callback is the function to perform the operation.
Private string add ()
{
Double addresult = double. parse (num1) + double. parse (num2 );
Return addresult. tostring ();
}

Private string sub ()
{
Double addresult = double. parse (num1)-double. parse (num2 );
Return addresult. tostring ();
}

Private string multi ()
{
Double addresult = double. parse (num1) * double. parse (num2 );
Return addresult. tostring ();
}

Private string Division ()
{
Double addresult = double. parse (num1)/double. parse (num2 );
Return addresult. tostring ();
}
}