Basic Applications of Lua and Delphi

Basic usage of Lua.
1. Open Lua:
VaR L: plua_state; </P> <p> // open Lua <br/> L: = lua_open; </P> <p> // you can continue to load the Lua standard library <br/> lua_baselibopen (l); <br/> lua_iolibopen (L ); <br/> lua_strlibopen (l); <br/> lua_mathlibopen (l); <br/>

2. After running, you must turn off:
Lua_close (L );

3. Add a method in Lua to pass function parameters to the Host Program. For example, add the print ("mrlong") method to the Lua script, which must be defined as follows:
Function luaprint (L: plua_state): integer; cdecl; <br/> var <br/> I, n: integer; <br/> begin <br/> N: = lua_gettop (l); // n = Total number of function parameters obtained <br/> for I: = 1 to n do <br/> showmessage (lua_tostring (L, i); <br/> result: = 0; <br/> end;

In the Lua script, you can use the print ("hello", "world", "USD") function to transmit data to the Host Program for processing.

 

4. Add a method in Lua to pass the host program variables to Lua, such as getuserid (), which can be defined as follows:

Function luagetuserid (L: lua_state): integer; cdecl; <br/> begin <br/> lua_pushnumber (L, 10000000); // the return value is 10000000, push 30 to the stack <br/> // lua_pushstring (L, 'usd000000'); // or return 'usd000000' <br/> result: = 1; // define the number of returned parameters, which is not a specific value. The value is 1 <br/> end;

In the Lua script, you can use the getuserid () function to obtain a value of 10000000.

5. After activating Lua, the registration method is as follows:

Lua_register (L, 'print ', luaprint );

Lua_register (L, 'getuserid', luagetuserid );

 

6. Load script:

// Load the script <br/> lual_loadfile (L, 'testscript. lua'); // load the script file to the memory <br/> If (lua_resume (L, 0) <> 0) then begin // execute the script loaded into the memory <br/> showmessage ('err'); <br/> end;

 

7. Retrieve the parameters of the registration method: for example, print ("mrlong") is used in the right Lua script. In this case, when I want to retrieve mrlong, I will use it.
S: = lua_tostring (L, 1); // note that this is from 1, not both 0 and Delphi and C/C ++. /
If (lua_gettop (l) <> 2) then // Where lua_gettop (l) is the data of the retrieved Parameter
Lual_error (L, 'number of parameter errors ');

Resource: http://luaforge.net/frs? Group_id = 157 & release_id = 706