addCustomFunction Method

Adds a custom function.

Syntax

Javascript (Usage)
Javascript (Specification)

var instance = new GC.Spread.Sheets.Worksheet(name);
var value; // Type: any
value = instance.addCustomFunction(fn);

function addCustomFunction( 
   fn : Function
) : any;

Parameters

fn: The function to add.

Example

These examples create custom functions.

Javascript

function FactorialFunction() {
    this.name = "FACTORIAL";
    this.maxArgs = 1;
    this.minArgs = 1;
}
FactorialFunction.prototype = new GC.Spread.CalcEngine.Functions.Function();
FactorialFunction.prototype.evaluate = function () {
    var result = 1, args = arguments;
    if (args.length === 1 && !isNaN(parseInt(args[0]))) {
        for (var i = 1; i < args[0]; i++) {
            result = i * result;
        }
        return result;
    }
    return "#VALUE!";
}

var factorial = new FactorialFunction();
activeSheet.addCustomFunction(factorial);
activeSheet.getCell(0,0).formula("factorial(5)");
var name = activeSheet.getCustomFunction("factorial");
alert(name);

Javascript

// Type =factorial(5) in a cell to see the result
function FactorialFunction() {
    this.name = "FACTORIAL";
    this.maxArgs = 1;
    this.minArgs = 1;
}
FactorialFunction.prototype = new GC.Spread.CalcEngine.Functions.Function();
FactorialFunction.prototype.evaluate = function () {
    var result = 1, args = arguments;
    if (args.length === 1 && !isNaN(parseInt(args[0]))) {
        for (var i = 1; i < args[0]; i++) {
            result = i * result;
        }
        return result;
    }
    return "#VALUE!";
}

var factorial = new FactorialFunction();
activeSheet.addCustomFunction(factorial);

Javascript

<!DOCTYPE html>
<html>
<head>
    <title>SpreadJS V10 Development Sample</title>
    <link href="http://cdn.grapecity.com/spreadjs/hosted/css/gc.spread.sheets.excel2016colorful.10.x.x.css" rel="stylesheet" type="text/css"/>
    <script src="https://code.jquery.com/jquery-2.1.1.min.js" type="text/javascript"></script>
    <script type="text/javascript" src="http://cdn.grapecity.com/spreadjs/hosted/scripts/gc.spread.sheets.all.10.x.x.min.js"></script>
    <script type="text/javascript">
        function CustomFunctionWithoutContext() {
            this.name = "FactorialAfterSum";
            this.maxArgs = 255;
            this.minArgs = 1;
        }
        CustomFunctionWithoutContext.prototype = new GC.Spread.CalcEngine.Functions.Function();
        CustomFunctionWithoutContext.prototype.description = function () {
            return {
                description: "The function returns the factorial of the sum result",
                parameters: [{
                    name: "value",
                    repeatable: true,
                    optional: true
                }],
            }
        }
        CustomFunctionWithoutContext.prototype.evaluate = function () {
            //If the isContextSensitive return false.
            //The arguments of evaluate will be the real function args.
            //For example, =XXXFunction(1,2,3,4,5), the arguments will be 1,2,3,4,5.
            //Hence, for this case, if you use =FactorialAfterSum(1,2,3), the arguments will be 1,2,3
            if (arguments.length > 0) {
                var sum = 0, factoral = 1;
                //Calc Sum
                for (var i = 0; i < arguments.length; i++) {
                    if (!isNaN(arguments[i])) {
                        sum += parseInt(arguments[i]);
                    }
                }
                //Calc factoral
                do {
                    factoral *= sum;
                } while (--sum >= 1)
                return factoral;
            }
            return GC.Spread.CalcEngine.CalcError.parse("#Value!");
        }





        function CustomFunctionWithContext() {
            this.name = "FactorialAfterSum2";
            this.maxArgs = 255;
            this.minArgs = 1;
        }
        CustomFunctionWithContext.prototype = new GC.Spread.CalcEngine.Functions.Function();
        CustomFunctionWithContext.prototype.description = function () {
            return {
                description: "The function returns the factorial of sum result",
                parameters: [{
                    name: "value",
                    repeatable: true,
                    optional: true
                }],
            }
        }
        CustomFunctionWithContext.prototype.evaluate = function () {
            //If the isContextSensitive return true.
            //The first argument will be evaluateContext, used for function calculation.
            //The following arguments will be the real function args.
            //For example, =XXXFunction(1,2,3,4,5), the arguments will be context, 1, 2, 3, 4, 5.
            //Hence, for this case, if customer use =FactorialAfterSum2(1,2,3), the arguments will be context, 1,2,3
            if (arguments.length >= 1) {
                var sum = 0, factoral = 1, context = arguments[0];
                //Calc Sum
                for (var i = 1; i < arguments.length; i++) {
                    if (!isNaN(arguments[i]) && arguments[i] !== null) {
                        sum += parseInt(arguments[i]);
                    }
                }
                //Calc factoral
                do {
                    factoral *= sum;
                } while (--sum >= 1)
                return factoral;
            }
            return GC.Spread.CalcEngine.CalcError.parse("#Value!");
        }
        CustomFunctionWithContext.prototype.isContextSensitive = function () {
            return true;
        }


        $(document).ready(function () {
            var spread = new GC.Spread.Sheets.Workbook(document.getElementById("ss"));
            var sheet = spread.getActiveSheet();
            sheet.addCustomFunction(new CustomFunctionWithContext());
            sheet.addCustomFunction(new CustomFunctionWithoutContext());

            sheet.setValue(0,0,1);
            sheet.setValue(1,0,2);
            sheet.setValue(2,0,3);
            sheet.setFormula(4,1,"=FactorialAfterSum2(1,2,3)");
            sheet.setFormula(5,1,"=FactorialAfterSum2(A1,A2,A3)");
        });
    </script>
</head>
<body>
<div id="ss" style="width:70%;height:500px;border: 1px solid gray;font-size:10.5pt"></div>
</body>
</html>

Reference

Worksheet type