<!DOCTYPE ?HTML><html ><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8" /><title>系好安全帶,準(zhǔn)備啟航</title><script type="text/javascript">var mydate = new Date();? var i = ["星期日","星期一","星期二","星期三","星期四","星期五","星期六"]? document.write("今天是陽歷:"+mydate.getFullYear() + "年" + mydate.getMonth() + "月" + mydate.getDay() + "日" + i[mydate.getDay()]+"<br ?/>");? //通過javascript的日期對象來得到當(dāng)前的日期,并輸出。??? ? //成績是一長竄的字符串不好處理,找規(guī)律后分割放到數(shù)組里更好操作哦? var scoreStr = "小明:87;小花:81;小紅:97;小天:76;小張:74;小小:94;小西:90;小伍:76;小迪:64;小曼:76";?var myarr = scoreStr.split(";");?for(var i=0;i<myarr.length;i++){? document.write(myarr[i]+"<br ?/>");}var sum =0;?for(var i=0;i<myarr.length;i++){? sum = sum + parseInt(myarr[i].slice(3));}document.write("該班級總分是:"+sum+"改班級平均分是:"+parseInt(sum/myarr.length));? //從數(shù)組中將成績撮出來,然后求和取整,并輸出。??</script></head><body></body></html>以下是疑問???? sum = sum + parseInt(myarr[i].slice(3)那位大神詳細(xì)解釋一下 ? ? ? ??小明:87 ?不是只有3個元素嘛 ?下標(biāo)應(yīng)該是0到2啊 ? slice(3)正么成立的呢 ?
關(guān)于對Javascript 7-23編程練習(xí) 日月星辰海同學(xué)代碼 理解 存在疑問 求指導(dǎo)
杰猛人
2015-10-10 22:14:39