从文件php中读取可变行数[关闭]

Question

How do I read specific number of lines from a txt file? For example I have a txt file which has 100 lines, and I need to print 25 or 50 lines to my website? I searched website and was not able to find how to do this using php or javascript. Thanks!

For now I have

<?php
                    if( isset($_GET['submit']) )
                    {

                        $pavadinimas = htmlentities($_GET['pavadinimas']);



                        $result = Myfunction($pavadinimas);



                        $string = file_get_contents("istorija.txt");
                        $array = explode(PHP_EOL, $string);

                        function Myfunction($pavadinimas){

                        For($i=0;$i<=$pavadinimas($array);$i++){
                        echo $array[$i] ."<br>
";
                        }
                        }
                    }
                    ?>

                    <?php if( isset($result) ) echo $result; //print the result above the form ?>

                    <form action="administratorius.php" method ="GET" >
                    Įrašų skaičius:
                    <input type="text" name="pavadinimas" maxlength="30" value="<?php echo $form->value("pavadinimas"); ?>"> <br>

                    <input type="submit" name="submit"  value="Prideti">
                    </form>

I want that my input would be as a variable for function. How do I make it work? Thanks!

Answer 1

You need to explode the string on [return].

$string = file_get_contents("file.txt");
$array = explode(PHP_EOL, $string);

Edit: EOL is better. Had forgot about it.
Edit2:

For($i=0;$i<=count($array);$i++){
     echo $array[$i] ."<br>
";
}

This above code will output the full textfile.
$i=0 means start at first line.
$i<=count($array) keep going till end of file. This can be changed to $i<=15 and you only output 15 lines.
$i++ means count up with one at the time.

And then there is a echo to output the linenumber $i

EDIT: I'm not sure what you are trying to do. But this is my best guess of your code:

if( isset($_GET['submit']) ){
      $pavadinimas = htmlentities($_GET['pavadinimas']);
      $result = Myfunction($pavadinimas, 25); //reads 25 rows of the pavadinimas
      $string = file_get_contents("istorija.txt");
      $array = explode(PHP_EOL, $string);

      $result2 = Myfunction($string, 50); // reads 50 rows of istorija.txt

      function Myfunction($pavadinimas,$NoOfRows){
           For($i=0;$i<=$NoOfRows;$i++){
                 $returnstr .= $pavadinimas[$i] ."<br>
"; // this appends the $returnstr with the next row
           }
           return $returnstr; // returns it to where the function was called.
      }
}

Now $result and $result2 are 25/50 rows of each variable (pavadinimas/string).

You have not given me alot to go on to what you want, your code is beyond what I understan. But this is probably what you wanted.