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                        /JavaScript進(jìn)階篇

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<!DOCTYPE?html><html><head><title>?事件</title>??<script?type="text/javascript">function?count(){//獲取第一個(gè)輸入框的值var?t1?=?document.getElementById("txt1").value;????//獲取第二個(gè)輸入框的值????var?t2?=?document.getElementById("txt2").value;????//獲取選擇框的值????var?o1?=?document.getElementById("select").value;????//獲取通過下拉框來選擇的值來改變加減乘除的運(yùn)算法則????//設(shè)置結(jié)果輸入框的值var?r1?=?"?";switch?(o1){case?"+":r1?=?parseInt(t1)?+?parseInt(t2);break;case?"-":r1?=?parseInt(t1)?-?parseInt(t2);break;case?"*":r1?=?parseInt(t1)?*?parseInt(t2);break;case?"/":r1?=?parseInt(t1)?/?parseInt(t2);break;}document.getElentById("fruit")?=?r1;}</script></head><body><input?type='text'?id='txt1'?/><select?id='select'>????????<option?value='+'>+</option>????????<option?value="-">-</option>????????<option?value="*">*</option>????????<option?value="/">/</option></select><input?type='text'?id='txt2'?/><input?type='button'?value='?=?'?onclick=count()?/>?<!--通過?=?按鈕來調(diào)用創(chuàng)建的函數(shù)，得到結(jié)果--><input?type='text'?id='fruit'?/>??</body></html>