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灭绝师太Correction status：qualified
Teacher's comments：计算器作业可以更简单，参考我发到群里的0806预习资料 1-cal.php脚本
Collection
Collection
<?php// 方法$arr=[23,3,45,6,78,8,34,88,23,55];$newarr=[];foreach($arr as $key=>$value){if($key%2==0){array_push($newarr,$arr[$key]);}}var_dump($newarr);//封装函数function getNewArrayByEeven($arr){$newarr=[];foreach($arr as $key=>$value){if($key%2==0){array_push($newarr,$arr[$key]);}}return $newarr;}var_dump(getNewArrayByEeven($arr));?>
<html ><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8" /><title>简单的计算器</title></head><body><form method="post" action="">数1：<input type="text", name="n1" />+数2：<input type="text", name="n2" />=<input type="submit" name="sub1" value="计算加法" /><p><?php //这段是加法代码段if(isset($_POST['sub1']))//这是一个点击事件，当点击了sub1时候，执行下面的代码{$sub1=$_POST['n1']+$_POST['n2'];//获取将前面的两个框的值，相加赋值给$sub1;echo $_POST['n1'].'+'.$_POST['n2'].'='.$sub1;//输出结果}?><p><form method="post" action="">数1：<input type="text" name="n3" />-数2：<input type="text" name="n4" />=<input type="submit" name="sub2" value="计算减法" /><p><?php //这段是减法代码段if(isset($_POST['sub2']))//点击事件{$sub2=$_POST['n3']-$_POST['n4'];//获取相应的值echo $_POST['n3'].'-'.$_POST['n4'].'='.$sub2;}?><p><form method="post" action="">数1：<input type="text" name="n5" />*数2：<input type="text" name="n6" />=<input type="submit" name="sub3" value="计算乘法" /><p><?php //这是乘法的代码段if(isset($_POST['sub3'])){$sub3=$_POST['n5']*$_POST['n6'];echo $_POST['n5'].'*'.$_POST['n6'].'='.$sub3;}?><p><form method="post" action="">数1：<input type="text" name="n7" />/数2：<input type="text" name="n8" />=<input type="submit" name="sub4" value="计算除法" /><p><?php //这是除法代码段if(isset($_POST['sub4'] )){$sub4=$_POST['n7']/$_POST['n8'];echo $_POST['n7'].'/'.$_POST['n8'].'='.$sub4;}?>
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