基于JavaScript的公式解释器 - 9 【逻辑操作符的实现】

逻辑操作符的基类型

逻辑操作符包括一元和二元类型，因此有两个基类型

文件：OperatorLogicBase.js

function OperatorBinaryLogicBase() { this.DeriveFrom(new OperatorBinaryBase()); this.set_ClassName("OperatorBinaryLogicBase"); this.set_Sign("undefined");};function OperatorUnaryLogicBase() { this.DeriveFrom(new OperatorUnaryBase()); this.set_ClassName("OperatorUnaryLogicBase"); this.set_Sign("undefined");};

 

逻辑操作符的实现

文件:OperatorLogic.js

function OperatorLogicAnd() { this.DeriveFrom(new OperatorBinaryLogicBase()); this.set_ClassName("OperatorLogicAnd"); this.set_Sign("&&");};OperatorLogicAnd.prototype.Evaluate = function(operands) { var values = this._getTwoNumberOperands(operands); return new OperandBoolean(values[0].get_Value() && values[1].get_Value());};function OperatorLogicOr() { this.DeriveFrom(new OperatorBinaryLogicBase()); this.set_ClassName("OperatorLogicOr"); this.set_Sign("||");};OperatorLogicOr.prototype.Evaluate = function(operands) { var values = this._getTwoNumberOperands(operands); return new OperandBoolean(values[0].get_Value() || values[1].get_Value());};function OperatorLogicNot() { this.DeriveFrom(new OperatorUnaryLogicBase()); this.set_ClassName("OperatorLogicOr"); this.set_Sign("!");};OperatorLogicNot.prototype.Evaluate = function(operands) { var val = this.GetOneNumberOperand(operands); return new OperandBoolean(!val.get_Value());};