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This time I will show you how to implement a simple calculator in HTML. What are the precautions for implementing a simple calculator in HTML? The following is a practical case, let's take a look.
<!DOCTYPE html> <html> <meta name="content-type" content="text/html; charset=UTF-8"> <head> <title>Calculator</title> <!--将按键内容以 字符串 形式存储在文字框中当按钮为“=”时,调用eval方法计算结果然后将结果输出文字框中--> <script type="text/ javascript "> var numresult; var str; function onclick num(nums) { str = document .getElementById("nummessege"); str.value = str.value + nums; } function onclickclear() { str = document.getElementById("nummessege"); str.value = ""; } function onclickresult() { str = document.getElementById("nummessege"); numresult = eval(str.value); str.value = numresult; } </script> </head> <body bgcolor="affff" > <!--定义按键表格,每个按键对应一个事件触发--> <table border="1" align="center" bgColor="#bbff77" style="height: 350px; width: 270px"> <tr> <td colspan="4"> <input type="text" id="nummessege" style="height: 90px; width: 350px; font-size : 50px" /> </td> </tr> <tr> <td> <input type="button" value="1" id="1" onclick="onclicknum(1)" style="height: 70px; width: 90px; font-size: 35px"> </td> <td> <input type="button" value="2" id="2" onclick="onclicknum(2)" style="height: 70px; width: 90px; font-size: 35px"> </td> <td> <input type="button" value="3" id="3" onclick="onclicknum(3)" style="height: 70px; width: 90px; font-size: 35px"> </td> <td> <input type="button" value="+" id="add" onclick="onclicknum('+')" style="height: 70px; width: 90px; font-size: 35px"> </td> </tr> <tr> <td> <input type="button" value="4" id="4" onclick="onclicknum(4)" style="height: 70px; width: 90px; font-size: 35px"> </td> <td> <input type="button" value="5" id="5" onclick="onclicknum(5)" style="height: 70px; width: 90px; font-size: 35px"> </td> <td> <input type="button" value="6" id="6" onclick="onclicknum(6)" style="height: 70px; width: 90px; font-size: 35px"> </td> <td> <input type="button" value="-" id="sub" onclick="onclicknum('-')" style="height: 70px; width: 90px; font-size: 35px"> </td> </tr> <tr> <td> <input type="button" value="7" id="7" onclick="onclicknum(7)" style="height: 70px; width: 90px; font-size: 35px"> </td> <td> <input type="button" value="8" id="8" onclick="onclicknum(8)" style="height: 70px; width: 90px; font-size: 35px"> </td> <td> <input type="button" value="9" id="9" onclick="onclicknum(9)" style="height: 70px; width: 90px; font-size: 35px"> </td> <td> <input type="button" value="*" id="mul" onclick="onclicknum('*')" style="height: 70px; width: 90px; font-size: 35px"> </td> </tr> <tr> <td colspan="2"> <input type="button" value="0" id="0" onclick="onclicknum(0)" style="height: 70px; width: 190px; font-size: 35px"> </td> <td> <input type="button" value="." id="point" onclick="onclicknum('.')" style="height: 70px; width: 90px; font-size: 35px"> </td> <td> <input type="button" value="/" id="division" onclick="onclicknum('/')" style="height: 70px; width: 90px; font-size: 35px"> </td> </tr> <tr> <td colspan="2"> <input type="button" value="Del" id="clear" onclick="onclickclear()" style="height: 70px; width: 190px; font-size: 35px" /> </td> <td colspan="2"> <input type="button" value="=" id="result" onclick="onclickresult()" style="height: 70px; width: 190px; font-size: 35px" /> </td> </tr> </table> </body> </html>I believe you have mastered the methods after reading these cases. For more exciting information, please pay attention to other related articles on the php Chinese website! Related reading:
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