Introduction to strtr string replacement in PHP_PHP tutorial

This article introduces the strtr string replacement in PHP. Friends who need to learn can refer to this article in detail. ​

strtr(string,from,to)
Or strtr(string,array)

First, focus on the first method of strtr function
Let’s take a look at the following example:

The code is as follows

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代码如下	复制代码
echo strtr("I Love you","Lo","lO"); ?> 得到的结果是 1 I lOve yOu

echo strtr("I Love you","Lo","lO");

?>

The result obtained is

1 I lOve yOu

代码如下	复制代码
echo strtr("I Love you","Love",""); ?> 结果是 I Love you

This result reminds us

1.strtr It is case sensitive
2. The replacement of strtr is very special. Pay attention to the yOu at the back. The O in the middle is replaced. This is obviously not our intention

Give another special example to illustrate the weirdness of this php sttr function

The code is as follows

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代码如下	复制代码
echo strtr("I Loves you","Love","lOvEA"); ?> 结果是 1 I lOvEs yOu

echo strtr("I Love you","Love","");

?>

The result is

I Love you

Nothing will change, so strtr needs to pay attention to:
3. It cannot be replaced by empty, that is, the last parameter cannot be an empty string, of course, spaces are allowed.

Another example of another case of strtr function

The code is as follows

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echo strtr("I Loves you","Love","lOvEA");
?>

代码如下	复制代码
$table_change = array('you'=>'her sister'); echo strtr("I Love you",$table_change); ?>

The result is

1 I lOvEs yOu

Note that A in the third parameter does not appear in the result
4. I don’t recommend using strtr to exchange less for more

代码如下	复制代码
$table_change = array('you'=>'her sister'); $table_change += array('Love' => 'hate'); echo strtr("I Love you",$table_change); ?>

ok, since this strtr function is quite troublesome, why do you still use it? The reason is, it’s fast It is said that strtr is four times faster than str_replace So 5. Be sure to use when you can use the strtr function How to use it comfortably? This is its second case strtr(string,array) 6. How to use strtr according to your wishes

The code is as follows	Copy code
$table_change = array('you'=>'her sister'); echo strtr("I Love you",$table_change); ?>

The result is I Love her sister 7. Tips: Just add whatever you want to replace to the array For example

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$table_change = array('you'=>'her sister'); $table_change += array('Love' => 'hate'); echo strtr("I Love you",$table_change); ?>

The result is
I hate her sister

Remind me again that writing Love as love will not work.

Okay, I talked about it in a messy way. In fact, what I want to say most about strtr is the usage behind it
Simple and convenient.
It seems that the later usage also ignores the problem of different character lengths before and after

The above PHP strtr function experiment, PHP5.2 test passed.

The code is as follows

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代码如下	复制代码
//这个时候输出的为baicai而不是bai123cai,因为str("pao")("bai123") echo strtr("paocai!","pao","bai123"); ?>

//The output at this time is baicai instead of bai123cai, because str("pao")("bai123")

echo strtr("paocai!","pao","bai123");

?>

代码如下	复制代码
//这个时候输出的为laocai而不是lacai,因为str("pao")>strlen("la")   echo strtr("paocai!","pao","la");   ?>

Example 2: When the length of the replaced value is smaller than the replaced target

The following is the quoted content:

The code is as follows

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代码如下	复制代码
$Arr=array('ao'=>'oa','ai'=>'ia'); echo strtr("paocai!",$Arr); //这个时候输出的为poacia ?>

//The output at this time is laocai instead of lacai, because str("pao")>strlen("la")

echo strtr("paocai!","pao","la");

?>

代码如下	复制代码
echo str_replace("you","paocai","I love you!"); //会输出I love paocai! ?>

Example 3: Support array replacement

The following is the quoted content:

The code is as follows	Copy code
$Arr=array('ao'=>'oa','ai'=>'ia'); echo strtr("paocai!",$Arr); //The output at this time is poacia ?>

Followed by str_replace: The following is the quoted content:

The code is as follows	Copy code
echo str_replace("you","paocai","I love you!"); //will output I love paocai! ?>

For more details, please see: http://www.bkjia.com/phper/18/strtr_str_replace.htm http://www.bkjia.com/PHPjc/445303.htmlwww.bkjia.comtruehttp: //www.bkjia.com/PHPjc/445303.htmlTechArticleThis article introduces the strtr string replacement in PHP. Friends who need to learn can refer to this article in detail. strtr(string,from,to) or strtr(string,array) First for the strtr function...