Javascript計算星座

今天看群里一哥們折騰得挺熱乎，手癢隨便寫了一個DEMO，供初學者參考。

重點，寫程序先定注釋，明確思路后再寫具體代碼。

 

//星座定義
var constellations = [
    {"Start":121,"End":220,"Name":"水平座"},    {"Start":221,"End":320,"Name":"雙魚座"},
    {"Start":321,"End":420,"Name":"白羊座"},    {"Start":421,"End":520,"Name":"金牛座"},
    {"Start":521,"End":620,"Name":"雙子座"},    {"Start":621,"End":720,"Name":"巨蟹座"},
    {"Start":721,"End":820,"Name":"獅子座"},    {"Start":821,"End":920,"Name":"處女座"},
    {"Start":921,"End":1020,"Name":"天秤座"},       {"Start":1021,"End":1120,"Name":"天蠍座"},    
    {"Start":1121,"End":1220,"Name":"射手座"}    ];
    
function WhatIsYourConstellation(y,m,d)
{
    /*
    判斷日期有效性
    1,3,5,7,8,10,12為31天
    2月潤年29，非潤年28
    4,6,9,11為30天
    */
    var daysInMonth = [31,99,31,30,31,30,31,31,30,31,30,31];
    
    //檢測年份
    if(y < 1970 || y > 2099) return "滾犢子1";
    
    //檢測月份
    if(m < 1 || m > 12) return "滾犢子2";
    
    //檢測日期
    var mDays = daysInMonth[m-1];
    //如果是二月，要根據年份計算天數，不是二月時略過此計算
    if(m == 2)
    {
        mDays = GetSpecialDays(y)
    }

    //判斷日數據是不是在月份的有效天范圍
    if(d < 0 || d > mDays)  return "滾犢子3";

    //好了，走到這一步，說明上面的驗證都TM過了。
    //這才判斷是哪一個星座
    //星座座標等於m*100 + d
    var pos = m * 100 + d;

    for(var i in constellations)
    {
        if(pos >= constellations[i].Start && pos <= constellations[i].End)
        {
            return constellations[i].Name;
        }
    }
}
//根據年份計算二月天數
function GetSpecialDays(y)
{
     if (y % 400 == 0 || (y % 4 == 0 && y % 100 != 0)) return 29;
     return 28;
}

 

調用DEMO

 

<meta http-equiv="content-type" content="text/html;charset=utf-8">
<script src="xx.js"></script>
<div id="log">

</div>
<script>
    function testCase(y,m,d)
    {
        var p = document.createElement("p");
        p.style.color = "red";
        p.style.fontSize = "14px";
        var data = WhatIsYourConstellation(y,m,d);
        p.innerText = y  + "年" + m + "月" + d + "日的計算結果：" + data;
        document.getElementById("log").appendChild(p);
    }
    
    testCase(1800,1,1);
    testCase(2000,-1,1);
    testCase(2000,13,1);
    testCase(2000,1,-1);
    testCase(2000,1,32);
    testCase(2000,2,32);
    testCase(2000,2,29);
    testCase(2001,2,29);
</script>

測試結果