php - lin 上的未定义索引 : submit in E:\xampp\htdocs\FA2\search. php

Question

Undefined index: submit in E:\xampp\htdocs\FA2\search.php on line2

 <?php
 $button = $_GET [ 'submit' ];
  $search = $_GET [ 'search' ];
   if( !$button )
    echo "you didn't submit a keyword";
     else { 
     if( strlen( $search ) <= 1 )
      echo "Search term too short";
       else { 
       echo "You searched for <b> $search </b> <hr size='1' > </ br > ";
        mysql_connect( "localhost","root","") ;
         mysql_select_db("fa");
          $search_exploded = explode ( " ", $search );
           $x = 0;
            foreach( $search_exploded as $search_each ) {
                 $x++; 
                 $construct = ""; 
                 if( $x == 1 ) 
                 $construct .="keywords LIKE '%$search_each%'";
                  else $construct .="AND keywords LIKE '%$search_each%'";
                   }
                    $construct = " SELECT * FROM schoolname WHERE $construct ";
                     $run = mysql_query( $construct ); $foundnum = mysql_num_rows($run);
                      if ($foundnum == 0) 
                      echo "Sorry, there are no matching result for <b> $search </b>. </br> </br> 1. Try more general words. for example: If you want to search 'how to create a website' then use general keyword like 'create' 'website' </br> 2. Try different words with similar meaning </br> 3. Please check your spelling";
                       else { 
                       echo "$foundnum results found !<p>"; 

                       while( $runrows = mysql_fetch_assoc( $run ) ) { 
                       $title = $runrows ['title']; 
                       $desc = $runrows ['description']; 
                       $url = $runrows ['url']; 
                       echo "<a href='$url'> <b> $title </b> </a> <br> $desc <br> <a href='$url'> $url </a> <p>";
                        }
                    }
                }
            }
        ?>

表单代码:

<form action="search.php" method="get" enctype="multipart/form-data">
    <input class="wow fadeInRight" data-wow-delay="0.5s" type="text" name="search" placeholder="Seach School Here" required/>
    <input class="wow fadeInLeft" data-wow-delay="0.5s" type="submit" value="GET STARTED" name="submit"/>
</form>

Answer 1

当您执行 get 请求时，似乎未设置提交值，这使得为 null 并且您收到该错误。