JavaScript的Math对象计算器
摘要：本例用一个计算器的形式练习了JavaScript的Math对象（数学对象）的使用。
JavaScript代码
<script type="text/javascript">
var calc = {
first:0,
result:0,
init:function(){
this.first = parseFloat(document.getElementById("first").value);
},
setResult:function(){document.getElementById("result").value = this.result},
abs:function(){
this.init();
this.result = Math.abs(this.first);
this.setResult();
},
sin:function(){
this.init();
this.result = Math.sin(this.first/360 * Math.PI);
this.setResult();
},
cos:function(){
this.init();
this.result = Math.cos(this.first/360 * Math.PI);
this.setResult();
},
tan:function(){
this.init();
this.result = Math.tan();
this.setResult();
},
round:function(){
this.init();
this.result = Math.round(this.first);
this.setResult();
},
ceil:function(){
this.init();
this.result = Math.ceil(this.first);
this.setResult();
},
exp:function(){
this.init();
this.result = Math.exp(this.first);
this.setResult();
},
floor:function(){
this.init();
this.result = Math.floor(this.first);
this.setResult();
},
log:function(){
this.init();
this.result = Math.log(this.first);
this.setResult();
},
E:function(){
this.result = Math.E;
this.setResult();
},
PI:function(){
this.result = Math.PI;
this.setResult();
},
SQRT2:function(){
this.result = Math.SQRT2;
this.setResult();
},
SQRT1_2:function(){
this.result = Math.SQRT1_2;
this.setResult();
},
LN2:function(){
this.result = Math.LN2;
this.setResult();
},
LN10:function(){
this.result = Math.LN10;
this.setResult();
},
LOG2E:function(){
this.result = Math.LOG2E;
this.setResult();
},
LOG10E:function(){
this.result = Math.LOG10E;
this.setResult();
}
};
</script>
HTML代码
<form id="jisuanqi" action="#"> <p> <label for="first">数字：</label> <input id="first" type="text" /> </p> <p> <label for="result">结果：</label> <input id="result" type="text" disabled="disabled" /> </p> <button onclick="calc.abs();;return false;" value="绝对值" >绝对值</button> <button onclick="calc.sin();;return false;" value="sin" >sin</button> <button onclick="calc.cos();;return false;" value="cos" >cos</button> <button onclick="calc.tan();;return false;" value="tan" >tan</button> <button onclick="calc.round();;return false;" value="round" >round</button> <button onclick="calc.ceil();;return false;" value="ceil" >ceil</button> <button onclick="calc.exp();;return false;" value="exp" >exp</button> <button onclick="calc.log();;return false;" value="log" >log</button> <button onclick="calc.floor();;return false;" value="floor" >floor</button> <button onclick="calc.floor();;return false;" value="floor" >floor</button> <br /> <button onclick="calc.E();;return false;" value="E" >E</button> <button onclick="calc.PI();;return false;" value="PI" >PI</button> <button onclick="calc.SQRT2();;return false;" value="SQRT2" >SQRT2</button> <button onclick="calc.SQRT1_2();;return false;" value="SQRT1_2" >SQRT1_2</button> <button onclick="calc.LN2();;return false;" value="LN2" >LN2</button> <button onclick="calc.LN10();;return false;" value="LN10" >LN10</button> <button onclick="calc.LOG2E();;return false;" value="LOG2E" >LOG2E</button> <button onclick="calc.LOG10E();;return false;" value="LOG10E" >LOG10E</button> </form>
效果(可以自己美化一下使用哦)
