js實現一個簡易計算器

2019-11-19 11:06:00

字體：大中小

來源：轉載

供稿：網友

本文實例為大家分享了JS實現簡易計算器的具體代碼，供大家參考，具體內容如下

<!DOCTYPE html><html><head><title>14th_test</title><meta charset="gb2312"></head> <body><h1>這是一個標題</h1><p>以下是一個簡易計算器</p> <table border="1" style="position:center;"><tr><th>第一個數</th><td><input id="fir" type="text" /></td></tr> <tr><th>第二個數</th><td><input id="sec" type="text" /></td></tr> <tr><td colspan="2"><button type="button" οnclick="add()">+</button><button type="button" οnclick="substract()">-</button><button type="button" οnclick="multiply()">*</button><button type="button" οnclick="divide()">/</button></td></tr> <tr><td colspan="2"><p id="result"></p></td></tr></table> <script>var res; //保存計算結果function add(){var first = document.getElementById("fir").value;var second = document.getElementById("sec").value; res = Number(first) + Number(second);  //這里"+"兩端必須Number類型轉換，否則當成字符串連接 sent(res);} function substract(){var first = document.getElementById("fir").value;var second = document.getElementById("sec").value; res = first - second; sent(res);} function multiply(){var first = document.getElementById("fir").value;var second = document.getElementById("sec").value; res = first * second; sent(res);} function divide(){var first = document.getElementById("fir").value;var second = document.getElementById("sec").value; res = first / second; sent(res);} function sent(re){ document.getElementById("result").innerHTML = re;}</script></body></html>

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