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这个php代码有什么问题

html php

Casey Flynn · 技术社区 · 15 年前

由于某些原因,此php代码不会回显。我好像不明白为什么。

<?php
function prob1(){
    $sum1 = 0;
    for($i=1; $i<11; $i++){
        $sum1 = $sum1 + $i; 
    }
    echo "Sum of numbers 1 - 10 is:". $sum1;
}
prob1();
?>

有什么想法吗?

UPDATE: Here is the entire web page that it exists in.
<html>
<head><title>Lab 13</title></head>
<body>

<h1>Problem 1:</h1>

<?php
function prob1(){
    $sum1 = 0;
    for($i=1; $i<11; $i++){
        $sum1 = $sum1 + $i; 
    }
    echo "Sum of numbers 1 - 10 is:". $sum1;
}
prob1();
?>

<p>
A. This is a server-side program. The code is executed on a web server and the results are returned to the user as HTML.
<br />
B. You can use javascript to accomplish the same calculation. Javascript code is executed client-side; meaning the user's machine will execute the code and return the result.
<br />
C. There is no need to use PHP in a scenario like this. Calculations such as these are more efficiently executed client-side.
<br />
</p>

<h1>Problem 2</h1>

<?php

function prob2($x){
$y = 0;

if ($x<5)
{
    $y = pow($x, 3) + 5*($x, 2) + 3;
}
else
{
    $y = pow($x, 3) - 9*pow($x, 2) + 12;
}   

echo "For X=" . $x . " Y=" + $y;
}

prob2(3);
prob2(8);

?>

<p>A. Yes, you can write the same code using javascript. In this situation, it wouldn't be necessary to use php unless you wanted to hide the calculation from the user.</p>

</body>
</html>

5 回复 | 直到 15 年前

Ed Manet 15 年前

嗯,你想要1到10的和,但是你循环了16次。

    <?php
     function prob1(){
       $sum1 = 0;
       for($i=1; $i<=10; $i++){
          $sum1 += $i; 
       }
       echo "Sum of numbers 1 - 10 is:". $sum1;
     }
     prob1();
?>

ajreal 15 年前

问题: $i<16 = Sum of numbers 1 - 10 ?

<? function prob1() { echo "Sum of numbers 1 - 10 is ", array_sum(range(1,10)); } prob1();

更新

$y = pow($x, 3) + 5*($x, 2) + 3;

应该是

$y = pow($x, 3) + 5*pow($x, 2) + 3;

Ruel 15 年前

它起作用了。但你的标签错了,应该是 数字和1-15 ". 在这里: http://codepad.org/TEvtB1hL

Mike C 15 年前

你有个问题:

$y = pow($x, 3) + 5*($x, 2) + 3;

这条线应该是

$y = pow($x, 3) + 5*pow($x, 2) + 3;

在我修改之后,页面正常加载。

(同时 echo "For X=" . $x . " Y=" + $y; 应该是 echo "For X=" . $x . " Y=" . $y; ).

JAL 15 年前

PHP在服务器上运行不正常,或者它被保存为.htm文件,而不是.PHP。

执行此操作时,会出现一些解析错误。他们是:

Parse error: syntax error, unexpected ',' in /var/duck/dork.php on line 36

第36行是

$y = pow($x, 3) + 5*($x, 2) + 3;

它缺少一个 pow 5*之后。

接下来,看看这条线

echo "For X=" . $x . " Y=" + $y;

“+”应该是“.”,以便将$y连接到该字符串。更好的方法是,使用双引号作为模板。。并添加 <BR> 所以输出不在同一行上。

echo "For X=$x Y=$y <br>";

这是完整的工作代码。

<html>
<head><title>Lab 13</title></head>
<body>

<h1>Problem 1:</h1>

<?php
function prob1(){
    $sum1 = 0;
    for($i=1; $i<11; $i++){
        $sum1 = $sum1 + $i; 
    }
    echo "Sum of numbers 1 - 10 is: $sum1";
}
prob1();
?>

<p>
A. This is a server-side program. The code is executed on a web server and the results are returned to the user as HTML.
<br />
B. You can use javascript to accomplish the same calculation. Javascript code is executed client-side; meaning the user's machine will execute the code and return the result.
<br />
C. There is no need to use PHP in a scenario like this. Calculations such as these are more efficiently executed client-side.
<br />
</p>

<h1>Problem 2</h1>

<?php

function prob2($x){
$y = 0;

if ($x<5)
{
    $y = pow($x, 3) + 5*pow($x, 2) + 3;
}
else
{
    $y = pow($x, 3) - 9*pow($x, 2) + 12;
}   

echo "For X=$x Y=$y";
echo "<br>";
}

prob2(3);
prob2(8);

?>

<p>A. Yes, you can write the same code using javascript. In this situation, it wouldn't be necessary to use php unless you wanted to hide the calculation from the user.</p>

</body>
</html>