js版本计算器第三版
来源：互联网 发布：网管控制mac绑定 编辑：程序博客网 时间：2024/06/16 08:31
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"><html> <head> <title>计算器</title> <style type="text/css">input {width:50px;}#Backspace {width:120px;}#CE {width:110px;}#result {width:300px;} </style> <script type="text/javascript">function Calculator() {this.value = '';this.current = '';this.operator = '';this.process = function (code) {switch (code.toString()) {case '.' :case '0' :case '1' :case '2' :case '3' :case '4' :case '5' :case '6' :case '7' :case '8' :case '9' :this.setNum(code);break;case '+/-' :this.setSymbol();break;case 'CE' :this.clearResult();break;case 'C' :this.clearAll();break;case 'Backspace' : this.deleteOne();break;case 'sqrt' :case '+' :case '-' :case '*' :case '/' :case '=' :this.calculator(code);break;}}// 设置数字this.setNum = function(num) {var result = document.getElementById("result");var pointIndex = this.current.toString().indexOf('.');if (pointIndex >= 0 && num == '.') {// 己经包含小数点,不再添加return;}var maxLength = 32;if (pointIndex) {// 包含小数点时,最大位数为33maxLength = 33;}// 超出最大位数限制if (this.current.toString().length >= maxLength) {return;}if (this.current.toString() == '0' && num != '.') {// 输入的数非小数，去掉前面的0this.current = num;} else {this.current += "" + num;}result.value = this.current;}// 设置符号位this.setSymbol = function() {var result = document.getElementById("result");var num = new Number(result.value);var tmp = -num.valueOf();result.value = tmp;}// 清除结果,恢复为0this.clearResult = function() {var result = document.getElementById("result");result.value = '0';this.current = '';}// 清除结果,恢复为0，不清除符号this.clearAll = function() {var result = document.getElementById("result");result.value = '0';this.value = '';this.current = '';this.operator = '';}// 删除一位数this.deleteOne = function() {var result = document.getElementById("result");var tmp = result.value.length > 1 ? result.value.substr(0, result.value.length - 1) : 0;tmp = tmp == '-' ? 0 : tmp;result.value = tmp;this.current = tmp;}// 计算this.calculator = function(operator) {var result = document.getElementById("result");if (operator == 'sqrt') {if (result.value != "") {this.value = Math.sqrt(result.value);result.value = this.value;this.current = result.value;}} else {if (this.value != "" && this.current != "" && this.operator != '') {var firstNum = new Number(this.value).valueOf();var secondNum = new Number(this.current).valueOf();var value = 0;switch (this.operator) {case '+' :value = firstNum + secondNum;break;case '-' :value = firstNum - secondNum;break;case '*' :value = firstNum * secondNum;break;case '/' :value = firstNum / secondNum;break;}this.value = value;result.value = this.value.toString();} else {this.value = this.current == '' ? this.value : this.current;}if (operator == "=") {result.value = this.value == '' ? '0' : this.value;this.operator = '';} else {this.operator = operator;}this.current = '';}}}var c = new Calculator();document.onkeyup = function(e){var evt = (typeof e == "undefined") ? window.event : e;if ((evt.keyCode >= 48 && evt.keyCode <= 57 && !evt.shiftKey) ||(evt.keyCode >= 96 && evt.keyCode <= 105 && !evt.shiftKey)){ if (evt.keyCode > 57) {c.process(evt.keyCode - 96); } else {c.process(evt.keyCode - 48); }}else if ((evt.keyCode == 107 && !evt.shiftKey) || (evt.keyCode == 61 && evt.shiftKey) || (evt.keyCode == 187 && evt.shiftKey)){ c.process('+');}else if ((evt.keyCode == 109 && !evt.shiftKey) || (evt.keyCode == 189 && !evt.shiftKey)){ c.process('-');}else if ((evt.keyCode == 106 && !evt.shiftKey) || (evt.keyCode == 56 && evt.shiftKey)){ c.process('*');}else if ((evt.keyCode == 111 && !evt.shiftKey) || (evt.keyCode == 191 && !evt.shiftKey)){ c.process('/');}else if (evt.keyCode == 13 || (evt.keyCode == 61 && !evt.shiftKey) || (evt.keyCode == 187 && !evt.shiftKey)){ c.process('=');}else if ((evt.keyCode == 110 && !evt.shiftKey) || (evt.keyCode == 190 && !evt.shiftKey)){c.process('.');}else if (evt.keyCode == 27){ c.process('C');}else if (evt.keyCode == 8){c.process('Backspace');}return false;//alert(evt.keyCode);} </script> </head><body ><table border="0" width="300px"> <tr><td colspan="5"><input type="text" id="result" value="0" style="text-align:right;" readonly="readonly" /></td></tr><tr><td colspan="2"><input id="Backspace" type="button" value="Backspace" onclick="c.process(this.value)" /></td><td colspan="2"><input id="CE" type="button" value="CE" onclick="c.process(this.value)" /></td><td><input type="button" value="C" onclick="c.process(this.value)" /></td></tr><tr><td><input type="button" value="7" onclick="c.process(this.value)" /></td><td><input type="button" value="8" onclick="c.process(this.value)" /></td><td><input type="button" value="9" onclick="c.process(this.value)" /></td><td><input type="button" value="/" onclick="c.process(this.value)" /></td><td><input type="button" value="sqrt" onclick="c.process(this.value)" /></td></tr><tr><td><input type="button" value="4" onclick="c.process(this.value)" /></td><td><input type="button" value="5" onclick="c.process(this.value)" /></td><td><input type="button" value="6" onclick="c.process(this.value)" /></td><td><input type="button" value="*" onclick="c.process(this.value)" /></td><td><input type="button" value="%" onclick="c.process(this.value)" /></td></tr><tr><td><input type="button" value="1" onclick="c.process(this.value)" /></td><td><input type="button" value="2" onclick="c.process(this.value)" /></td><td><input type="button" value="3" onclick="c.process(this.value)" /></td><td><input type="button" value="-" onclick="c.process(this.value)" /></td><td><input type="button" value="1/x" onclick="c.process(this.value)" /></td></tr><tr><td><input type="button" value="0" onclick="c.process(this.value)" /></td><td><input type="button" value="+/-" onclick="c.process(this.value)" /></td><td><input type="button" value="." onclick="c.process(this.value)" /></td><td><input type="button" value="+" onclick="c.process(this.value)" /></td><td><input type="button" value="=" onclick="c.process(this.value)" /></td></tr></table></body></html>
