How to add variables to PHP string

This article mainly shares with you how to add variables to PHP strings. When defining a string, you can use single quotes or double quotes. My personal habit is to use double quotes. When outputting a string, if the string contains a string variable, there is a difference between using single quotes and double quotes. Such as the following program:

<?php$website = "NowaMagic";
$name = &#39;Gonn&#39;;echo &#39;Welcome to visit 
$website. My name is $name.&#39;;echo &#39;<br>&#39;;
echo "Welcome to visit $website. My name is $name.";

Program output:
Welcome to visit ##website.Mynamei swebsite.Mynameisname. Welcome to visit NowaMagic. My name is Gonn.
The output enclosed in single quotes does not parse the string variable, but the output enclosed in double quotes parses the variable and outputs the value of the variable.
Efficiency issues
It is generally believed that in string output that does not require variable parsing, using single quotes may be faster.
By the way, everyone knows that for pure strings that do not require variable substitution, because in C/C++, double quotes represent strings, so in this case, it is better to use double quotes. In addition, according to W3C standards, attribute values ​​in HTML should be enclosed in double quotes, so don't get used to single quotes and abuse them everywhere.
Teach you how to add variables to PHP strings

<?php   
    $temp = "hello"   
    echo "$temp world";

<?php   
    $temp = array("one" => 1, "two" => 2);   
    // 输出：: The first element is 1   
    echo "The first element is $temp[one].";

<?php   
    $temp = array("one" => 1, "two" => 2);   
    echo "The first element is {$temp["one"]}.";

When outputting a string, if the string contains a string variable, there is a difference between using single quotes and double quotes. Such as the following procedure:

<?php$website = "NowaMagic";$name = &#39;Gonn&#39;;echo &#39;Welcome to visit $website. 
My name is $name.&#39;;echo &#39;<br>&#39;;echo "Welcome to visit $website. My name is $name.";

程序输出：
Welcome to visit website.Mynameiswebsite.Mynameisname.
Welcome to visit NowaMagic. My name is Gonn.
用单引号括住的输出，并没有解析字符串变量，而使用双引号括住的输出，则解析了变量了，输出变量的值。
效率问题
普遍认为，在不需要变量解析的字符串输出，用单引号速度可能会快一些。
顺便说一句，对于不需要变量替换的纯字符串，大家都知道，因为在C/C++中，双引号才表示字符串，所以这种情况下，还是使用双引号的好。另外对于W3C标准来说， HTML中的属性值应该是使用双引号来包含的 ，所以不要习惯了单引号，到处滥用。
教你如何在PHP字符串中加入变量

我们在对PHP语言的学习时，都会熟练的掌握PHP字符串，那么在实际应用中，我们该如何向PHP字符串中加入变量呢？今天我们就为大家介绍了具体的解决办法。

<?php   
    $temp = "hello"   
    echo "$temp world";

但是需要对PHP字符串中加入变量说明的是，尽管下面的例子没有错误：

<?php   
    $temp = array("one" => 1, "two" => 2);   
    // 输出：: The first element is 1   
    echo "The first element is $temp[one].";

但是如果后面那个 echo 语句没有双引号引起来的话，就要报错，因此建议使用花括号：

<?php   
    $temp = array("one" => 1, "two" => 2);   
    echo "The first element is {$temp["one"]}.";

以上就是PHP字符串中加入变量的具体解决方法。

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