从mysql表获取行到php数组并将其传递给ajax

Question

I'm trying to get values from a regular table with regular way of mysql_query and mysql_fetch_array from ajax call in php

if ($comtype==3){
        $getsteps = mysql_query("SELECT id FROM steps WHERE id = $id");

        $row = mysql_fetch_array($getsteps);
        if($row != false){
            $steps_array = array();
            while ($row = mysql_fetch_array($getsteps, MYSQL_ASSOC)) 
            {
                array_push($steps_array,$row);
            }
            $countsteps = count($steps_array);

            error_log("count: ".$countsteps);
            error_log(print_r($steps_array));

            echo json_encode(array("comtype" => $comtype, "countsteps" => $countsteps, "steps" => $steps_array)); 
        } else {
            //error
        }
    }

in php error log :

[28-Aug-2017 11:25:32 UTC] count: 1 [28-Aug-2017 11:25:32 UTC] 1

while the count I know it is 2 rows!!!

and in ajax

$.ajax({
            type:'POST',
            url:'app/check.php',
            data: {'ID':ID},
            dataType: 'json',
            success: function(value){
                if (value.comtype== "0") {
                        $("#newC").show();
                        $("#hadC").hide();
                    } else {
                        var method;
                        var com;
                        com = "<div class='clearfix'></div><br><h3>old.</h3>";
                        com += "By Stpes: <br>";

                            for (i = 0; i < value.countsteps; i++) { 
                                com += "Step " + Number(i)+1 + ": Greater Than " + value.steps_array['calfrom'] + " AND Less Than or Equal " + value.steps_array['calto'] + " Apply "  + value.steps_array['calapl'] + " % <br>";
                            }
                        }

                        $("#hadC").html(com);
                        $("#hadC").show();
                        $("#newC").hide();
                    }
                }   
            });

question is: 1. I don't know how to push data from while into array? 2. I don't know how to loop into this array in ajax to view it in html div?

Answer 1

The problem is that you're calling mysql_fetch_array() before the while loop. This fetches the first row, and the loop fetches the remaining rows.

If you want to test whether any rows were returned before looping, call mysql_num_rows() . You can also use this instead of count($steps_array) .

if ($comtype==3){
    $getsteps = mysql_query("SELECT id FROM steps WHERE id = $id");

    $countsteps = mysql_num_rows($getsteps);
    if($countsteps > 0) {
        $steps_array = array();
        while ($row = mysql_fetch_array($getsteps, MYSQL_ASSOC)) 
        {
            array_push($steps_array,$row);
        }

        error_log("count: ".$countsteps);
        error_log(print_r($steps_array));

        echo json_encode(array("comtype" => $comtype, "countsteps" => $countsteps, "steps" => $steps_array)); 
    } else {
        //error
    }
}