str_replace()

(PHP 4, PHP 5, PHP 7)

子字符串替换

说明

该函数返回一个字符串或者数组。该字符串或数组是将$subject中全部的$search都被$replace替换之后的结果。

如果没有一些特殊的替换需求（比如正则表达式），你应该使用该函数替换ereg_replace()和preg_replace()。

参数

如果$search和$replace为数组，那么str_replace()将对$subject做二者的映射替换。如果$replace的值的个数少于$search的个数，多余的替换将使用空字符串来进行。如果$search是一个数组而$replace是一个字符串，那么$search中每个元素的替换将始终使用这个字符串。该转换不会改变大小写。

如果$search和$replace都是数组，它们的值将会被依次处理。

查找的目标值，也就是needle。一个数组可以指定多个目标。

$search的替换值。一个数组可以被用来指定多重替换。

执行替换的数组或者字符串。也就是haystack。

如果$subject是一个数组，替换操作将遍历整个$subject，返回值也将是一个数组。

如果被指定，它的值将被设置为替换发生的次数。

返回值

该函数返回替换后的数组或者字符串。

范例

Example #1str_replace()基本范例

Enjoy

$myString = “It was the best of mine it was the worst of mine,”;
// Displays “It was the best of bananas, it was the worst of bananas,”
echo str_replace( “mine”, “bananas”, $myString );
If you want to know how many times the search string was replaced, pass in a variable as an optional
fourth argument. After the function runs, this variable holds the number of replacements:
$myString = “It was the best of mine, it was the worst of mine,”;
// Displays “It was the best of bananas, it was the worst of bananas,”
echo str_replace( “mine”, “bananas”, $myString, $num ) . “  ”;
// Displays “The text was replaced 2 times.”
echo “The text was replaced $num times.  ”;

I was working with MySQL and displaying the title to things on the web page. I'd written a script to ensure single and double quotes were removed from the title. I used
  $title = str_replace( "'", "", $title );
and
   $title = str_replace( '"', "", $title );
But still the single and double quotes continued. So I wrote a bit of code to print out each character separated by a dash. Like so:
   for( $i=0; $i