贴上代码：
<?php error_reporting(E_ALL & ~E_NOTICE); $expression=$_GET['TrueTable']; //读取输入框数据 if(!empty($_GET['TrueTable'])){ $expression=strtoupper($expression); //将输入的小写字母，替代成大写字母 $expressionArr=str_split($expression); //将$expression转换成数组 foreach($expressionArr as $v){ //把字母放在 $varTotal数组中 if($v>='A' && $v<='Z'){ $varTotal[]=$v; } } $varTotal = array_unique($varTotal); //去掉$varTotal数组中重复的字母 sort($varTotal); //$varTotal数组中字母正向排序 $varTotal1 = preg_replace("/([A-Z])/","$\1",$varTotal); //$varTotal1数组中字母变成变量 $maxN = count($varTotal); //$expressionArr = preg_replace("/([A-Z])/","$\1",$expressionArr); //$expressionArr数组中字母变成变量 $newExpression=implode('',$expressionArr); //$expressionArr数组变成字符串 //echo $newExpression."<br />"; $newExpression= preg_replace("/([A-Z])->([A-Z])/","!\1|\2",$newExpression); $newExpression= preg_replace("/((.*?))->([A-Z])/","!\1|\2",$newExpression); $newExpression= preg_replace("/((.*?))->(.*?)/","!\1|\2",$newExpression); $newExpression= preg_replace("/([A-Z])->(.*?)/","!\1|\2",$newExpression); $expressionArr=str_split($newExpression); //将$expression转换成数组 $expressionArr = preg_replace("/([A-Z])/","$\1",$expressionArr); $newExpression=implode('',$expressionArr); //echo $newExpression; } ?> <!DOCTYPE html> <html> <head> <meta charset="utf-8" /> <title>真值表查询1.0 BY:小臻</title> </head> <body> <span style="color:red;text-align:center;"><h1>真值表查询1.0 BY:小臻</h1></span> <div style="500px;margin:30px auto 0 auto;text-align:center;"> <form action="" method="get"> <input type="text" name="TrueTable" value="<?php echo $_GET['TrueTable'] ?>"/> <input type="submit" value="确定"/> <br /> <br /> <!--<input type="reset" value="取消" /><br /><br /> <input type="button" value="∨" /> <input type="button" value="∧" /> <input type="button" value="┐" /> <input type="button" value="→" /> <input type="button" value="↔" /><br /><br />--> </form> <!--[ 说明：析取(∨) , 合取(∧) , 非(┐) , 蕴含(→) , 等价(↔) ]--> <p>[ 说明：析取(|) , 合取(&) , 非(!) , 蕴含(->) , 等价(=) ]</p> <table width="300px" style="margin:30px auto 0 auto;text-align:center;border:1px solid #000;"> <?php echo "<tr>"; if(!empty($_GET['TrueTable'])){ foreach($varTotal as $v){ echo "<td>{$v}</td>"; } echo "<td>结果</td>"; $result=pow(2,$maxN); for($i=0;$i<$result;$i++){ $resultN[$i]=sprintf("%0{$maxN}d",decbin($i)); $resultN[$i]=str_split($resultN[$i]); } foreach($resultN as $k=>$v){ echo "<tr>"; foreach($resultN[$k] as $k1=>$v1){ echo "<td>".$v1."</td>"; $varTotal2[$k1]=$varTotal1[$k1]."=".$v1; //echo $varTotal2[$k1]." "; eval($varTotal2[$k1].";"); } //echo $newExpression; eval("$varTotal3[] = ".$newExpression.";"); foreach($varTotal3 as $k2=>$v){ if($v==NULL){ $varTotal3[$k2]=0; } } echo "<td>".$varTotal3[$k]."</td>"; echo "</tr>"; } //print_r($varTotal3); } ?> </table> </div> </body> </html>