Difference between revisions of "Server Side Procedures - Parameter Passing Examples"

Revision as of 11:19, 13 February 2020

Overview

For an overview of using server side procedures with the Lianja Web Client and Lianja Cloud Server, see here.

Lianja/VFP Server Side Procedures

exports.conf

A function can be called directly if it is declared in exports.conf.

var result = mylibproc();

Lianja.evaluate()

The Lianja.evaluate() method can be used to call a Lianja/VFP function/procedure.

var result = Lianja.evaluate("myproc()");

To call a procedure in a library, prefix the procedure name with the library name and '::'.

var result = Lianja.evaluate("mylib::mylibproc()");

Note how to build up the string passed to Lianja.evaluate() when using local variables:

Numeric variables:

var num5 = 5;
var num6 = 7;
var result = Lianja.evaluate("mylib::mylibproc(" + num5 + "," + num6 + ")");

String variables (include quotes):

var num7 = "5";
var num8 = "7";
var result = Lianja.evaluate("mylib::mylibproc('" + num7 + "','" + num8 + "')");

Macro substitution with {} can be used on globals in the Web Client:

Numeric:

num1 = 5;
num2 = 7;
var result = Lianja.evaluate("mylib::mylibproc({num1},{num2})");

Strings (include quotes):

num3 = "5";
num4 = "7";
var result = Lianja.evaluate("mylib::mylibproc('{num3}','{num4}')");

FORMAT()

Lianja v5.3 introduced the format() function, which simplifies the preparation of Lianja.evaluate() call strings, e.g.

////////////////////////////////////////////////////////////////
// Event delegate for 'customsectionmenu' event
function page1_section1_customsectionmenu()
{
	var cnum1 = "5";
	var cnum2 = "7";
	// Pass as character values for the mylibproc() function in the mylib.prg server-side procedure library
	var evalstring = format("mylib::mylibproc('{0}','{1}')",cnum1,cnum2);
	var result = Lianja.evaluate(evalstring);
	field1.text = field1.text + "\n" + result;
 
	var num1 = 5;
	var num2 = 7;
	// Pass as numeric values for the mylibproc() function in the mylib.prg server-side procedure library
	var evalstring = format("mylib::mylibproc({0},{1})",num1,num2);
	var result = Lianja.evaluate(evalstring);
	field1.text = field1.text + "\n" + result;
};