js打印纸函数（递归）

    //打印纸尺寸，单位MM

    //http://en.wikipedia.org/wiki/ISO_216

    var page = function() {

        var A0 = { name: "A0", width: 841, height: 1189 }; //单位MM

        var B0 = { name: "B0", width: 1000, height: 1414 }; //单位MM

        var C0 = { name: "C0", width: 917, height: 1297 }; //单位MM

        //获取前一个规格

        function getPrefixSize(name) {

            var list = name.split('');

            var series = list[0];

            var number = parseInt(list[1]);

            if (!isNaN(number) && number > 0) {

                return series + (number - 1);

            }

        }

        //获取规格的尺寸

        function getSize(name) {

            if (name == "C7/6") {

                return { name: "C7/6", width: 81, height: 162 };

            }

            var list = name.split('');

            var series = list[0];

            var number = parseInt(list[1]);

            if (isNaN(number)) {

                return;

            }

            if (number == 0) {

                if (series == "A") { return A0; }

                else if (series == "B") { return B0; }

                else if (series == "C") { return C0; }

            }

            return { name: name, width: parseInt(getSize(getPrefixSize(name)).height / 2), height: parseInt(getSize(getPrefixSize(name)).width) };

        }

        return {

            getSize: getSize

        }

    } (); 

用法

page.getSize('A4')