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Using Smarty in PHP Part 4: Custom Variable Mediator_PHP Tutorial
- WBOYOriginal
- 2016-07-13 17:46:28845browse
In PHP, there are many functions for processing text. You can process the text you want to process through the function, then call assign() in the Smarty template engine to assign the value to a variable, and assign it to the template for display.
The variable mediator in Smarty is similar to the text processing function in PHP, but the syntax is different. In Smarty, it is directly followed by the mediator function name through "|". If there are parameters, they must be added after ":". If there are two parameters, just add them up.
Format: {$var|modifier1:"Parameter1":"Parameter2":Parameter3|modifier2|modifier3|...}
The file defining the mediator must be placed in Smarty, the specific path is: libs/plugins/. The file name must be in the Smarty format modifier.moderatorname.php
The following uses an example to demonstrate the use of custom variable mediators in Smarty
Program idea: Make two variable mediators. The functions are: one to convert text; one to intercept text.
init.inc.php (Smarty initialization file)
Define('ROOT_PATH', dirname(__FILE__)); //Set the website root directory
require ROOT_PATH.'/libs/Smarty.class.php'; //Load Smarty template engine
$_tpl = new Smarty(); //Create an instance object
$_tpl->template_dir = ROOT_PATH.'/tpl/'; //Set the template file directory
$_tpl->compile_dir = ROOT_PATH.'./com/'; //Set the compiled file directory
$_tpl->left_delimiter = '<{'; //Set the left delimiter
$_tpl->right_delimiter = '}>'; //Set the right delimiter
?>
index.php(main file)
define('CONST_VAR', 'ABC');
require 'init.inc.php'; //Introduce template initialization file
global $_tpl;
$_str = 'abcdEFGHigklmnOPQRSTuvwsYz'; //Define a string
$_tpl->assign('str',$_str); $_tpl->assign('str',$_str); //Assign string to str
$_tpl->assign('str1',strtolower($_str)); //Convert all strings to lowercase and assign them to str1
$_tpl->assign('str2',strtoupper($_str)); //Convert all strings to uppercase and assign them to str2
$_tpl->assign('str3',ucfirst($_str)); //Convert all strings to uppercase and assign them to str3
$_tpl->assign('str4',substr($_str, 0,15).'...');//Intercept the first 15 characters of the string, replace the following characters with '...', and assign Give str4
$_tpl->assign('str5',strtoupper(substr($_str, 0,15)).'...'); //Intercept the first 15 characters of the string and convert them to uppercase, and use '.. .' instead and assign it to str4
$_tpl->display('index.tpl'); //Introduce template
?>
tpl/index.tpl
<{$str}>
<{$str1}>
<{$str2}>
<{$str3}>
<{$str4}>
<{$str5}>
<{$str|transform:"lower"}>
<{$str|transform:"upper"}>
<{$str|transform:"firstdx"}>
<{$str|subString:0:15:"###"}>
<{$str|subString:0:15:"@@@"|transform:"upper"}>
<{$str|transform:"upper"|subString:0:15:"@@@"}>
/libs/plugins/modifier.transform.php (Transform File Modifier)
/**
* smarty_modifier_transform
* * Variable mediator function for string conversion
* @param string $string Processing string
* @param string $type Processing type
*/
Function smarty_modifier_transform($string,$type) {
switch ($type) {
case 'upper' :
$str = strtoupper($string);
break;
case 'lower' :
$str = strtolower($string);
break;
case 'firstdx' :
$str = ucfirst($string);
break;
default:
$str = $string;
}
return $str;
}
?>
lib/plugins/modifier.subString.php (interception text modifier)
/**
* smarty_modifier_subString
* Process interception string mediator
* @param string $string Processing string
* @param int $start_num Starting position, default starts from the beginning
* @param int $end_num End position, default 20
* @param string $addTo Append string, default '...'
*/
Function smarty_modifier_subString($string,$start_num=0,$end_num=20,$addTo='...') {
$_str = '';
If (strlen(substr($string, $start_num, $end_num))>=$end_num) {
$_str = substr($string, $start_num, $end_num).$addTo;
} else {
$_str = substr($string, $start_num, $end_num);
}
return $_str;
}
?>
Execution result:
The above example shows that the mediator file must be placed in Smarty's plug-in directory plugins, and the naming must follow Smarty's rules, so that the mediator function you write can be called. Another point that needs to be explained is that the defined function name must also comply with Smarty's default naming rules, for example: smarty_modifier_XXX, and a modifier file can only contain one function, not multiple.
… Regarding Smary’s built-in mediator, the next section will introduce it