Question

我在PHP中遇到了一个奇怪的问题。我正在解析一个网页，我得到了正在寻找的正确值。问题是，如果我想打印它们，一起形成一个“回声”，它只打印某些值，而其他值不打印。我举个例子，这不是我真正的代码，因为我不能在这里找到我的来源（这是很长的，我可以做一个较短的例子）。

<?php
 $variable1 = function_to_get_this_variable;
 $variable2 = function_to_get_this_variable;
 $variable3 = function_to_get_this_variable;
 $variable4 = function_to_get_this_variable;
 $variable5 = function_to_get_this_variable;
 $variable6 = function_to_get_this_variable;

现在，如果我单独打印每个值（即通过echo $ variable1;），我得到我正在寻找的值。但如果尝试将它们打印在一起，通过

echo("This is the variable 1: " . $variable1 . " This is the variable 2: " . $variable2 . " This is the variable 3 :" . $variable3 . " This is the variable 4: " . $variable4 . " This is the variable 5: " . $variable5 . " This is the variable 6: " . $variable6);

它只打印变量直到变量4，然后它不会打印任何内容。如果我只离开

echo(" This is the variable 5: " . $variable5 . " This is the variable 6: " . $variable6);

它只打印变量5.再次，如果只留下

echo(" This is the variable 6: " . $variable6);

正确打印第六个。

哪个可能是问题？此外，我记得你，我正在解析一个网页（如果它有用）。提前全部谢谢。

Answer 1

您只是缺少语音标记（您也可以删除()，echo是一种语言结构。）。

试试这个：

echo "This is the variable 1: " 
. $variable1 . " This is the variable 2: " 
. $variable2 . " This is the variable 3: "
. $variable3 . " This is the variable 4: " 
. $variable4 . " This is the variable 5: " 
. $variable5 . " This is the variable 6: " 
. $variable6 ;

根据@ mario的建议，您可以更轻松地使用插值，这意味着在双引号内将解析$变量。如果需要，请使用{}包围$变量。

Answer 2

首先......如果你使用双引号"，你可以这样做：

echo "This is the variable 1: $variable1 
      This is the variable 2: $variable2 
      This is the variable 3: $variable3 
      This is the variable 4: $variable4 
      This is the variable 5: $variable5 
      This is the variable 6: $variable6";

如果你想在var或array旁边使用特殊字符，你可以这样做：

echo "This is the variable 1: {$variable1} 
      This is the variable 2: {$variable2} 
      This is the variable 3: {$variable3} 
      This is the variable 4: {$variable4} 
      This is the variable 5: {$variable5} 
      This is the variable 6: {$variable6}";

使用"比'慢，因为解释器在""内查找变量。单引号解决方案在这里看起来像答案之一：

echo 'This is the variable 1: '
     . $variable1 . ' This is the variable 2: ' 
     . $variable2 . ' This is the variable 3: '
     . $variable3 . ' This is the variable 4: ' 
     . $variable4 . ' This is the variable 5: ' 
     . $variable5 . ' This is the variable 6: '
     . $variable6 ;

几乎忘了什么......没有多少人使用它，它比上面的例子更具可读性：

echo 'This is the variable 1: '.$variable1,
     'This is the variable 2: '.$variable2,
     'This is the variable 3: '.$variable3,
     'This is the variable 4: '.$variable4,
     'This is the variable 5: '.$variable5,
     'This is the variable 6: '.$variable6;

Answer 3

我认为你的陈述是错误的......

echo("This is the variable 1: " . $variable1 . " This is the variable 2: " . $variable2 . " This is the variable 3 : . $variable3 . " This is the variable 4: " . $variable4 . " This is the variable 5: " . $variable5 . " This is the variable 6: " . $variable6);

应该是：

echo("This is the variable 1: " . $variable1 . " This is the variable 2: " . $variable2 . " This is the variable 3 " . $variable3 . " This is the variable 4: " . $variable4 . " This is the variable 5: " . $variable5 . " This is the variable 6: " . $variable6);

您可能还想利用PHP的双引号变量扩展。我发现在这样的简单情况下它会有所帮助......

echo("This is the variable 1: $variable1 This is the variable 2: $variable2 This is the variable 3: $variable3 This is the variable 4: $variable4 This is the variable 5: $variable5 This is the variable 6: $variable6");

Answer 4

尝试使用 sprintf 而不是

$VarToPrint = sprintf("This is the variable 1: %s This is the variable 2: %s This is the variable 3: %s This is the variable 4: %s This is the variable 5: %s This is the variable 6: %s", $variable1, $variable2, $variable3, $variable4, $variable5, $variable6);

接下来你只需 echo $ VarToPrint;

PHP - Echo不打印某些值

4 个答案: