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Home Backend Development PHP Tutorial PHP echo [轉(zhuǎn)]

PHP echo [轉(zhuǎn)]

Jun 23, 2016 pm 02:36 PM

PHP 語言中,echo 是一個(gè)最常用的內(nèi)置函數(shù)。它的作用,就是輸出一個(gè)或者多個(gè)字符串。

用 echo 輸出一個(gè)字符串

在 PHP 語法中,我們已經(jīng)舉過一個(gè)簡(jiǎn)單的 echo 的示例,如下:

<html><body>  <?phpecho "Blabla.cn"?>  </body></html>  

返回的 HTML 結(jié)果是:

<html><body>Blabla.cn</body></html>  

我們將這個(gè)例子再寫復(fù)雜一點(diǎn),加上 HTML 標(biāo)記,如下:

<html><body><?phpecho "<h1>Blabla.cn</h1>"?></body></html>  

返回的 HTML 結(jié)果是:

<html><body><h1>Blabla.cn</h1></body></html>  
用 echo 輸出多個(gè)字符串

echo 也可以輸出多個(gè)字符串,用逗號(hào) DE<, DE<分隔。示例如下:

<html><body><?phpecho "woyouxian.net", " and ","blabla.cn"?></body></html>  

返回的顯示結(jié)果是:

woyouxian.net and blabla.cn  
用 echo 輸出變量的值

echo 還可以輸出變量的值。示例如下:

<html><body><?php$a = "blabla.cn";echo $a?></body></html>  

上面代碼中,$a 是一個(gè)變量,$a 的值是 "blabla.cn",用 echo 輸出 $a 的值。

顯示的結(jié)果是:

blabla.cn  

再比如,輸出兩個(gè)變量的值:

<html><body><?php$a = "woyouxian.net ";  $b = "blabla.cn";echo $a,$b?></body></html>  

返回的顯示結(jié)果是:

woyouxian.net blabla.cn  
echo 的字符串參數(shù)里含有變量

如果 echo 的字符串參數(shù)里含有變量,有兩種情況:第一種是字符串參數(shù)用雙引號(hào),echo 輸出變量的值;第二種是字符串參數(shù)使用單引號(hào),則輸出變量名。

字符串采用雙引號(hào)的示例如下:

$a = "just in case";  echo "take the gun,$a";  

返回的結(jié)果是:

take the gun,just in case  

上例中,字符串采用雙引號(hào),在字符串里的變量輸出變量的值。

再看字符串用單引號(hào)的情況。示例如下:

$a = "just in case";echo 'take the gun,$a';  

在字符串使用單引號(hào)的情況下,返回的結(jié)果是輸出變量名稱,而不是變量的值:

take the gun,$a  
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