Three ways to remove the last character of a string in a PHP program

Common syntax formats:

foreach ($arr as $key = = $value) {
$arr _str = $arr [' x_id ']. ‘,‘ . $arr _str;
}

Assume that the characters in the character array $arr are

Arr[0] = ' a ';
Arr[1] = ' B ';
ARR[2] = ' C ';

Then, after the concatenation of the $arr _str string is a,b,c, this time, we need to the last character ', ' to delete processing.

Two ways to remove the last character in PHP are summarized:

Method One:

substr ($arr _str,0,strlen ($arr _str)-1);
Explanation: substr () function syntax: string substr (string $string, int $start [, int $length])

strlen () function syntax: int strlen (string $string)

This example principle:
First use the strlen () function to determine the length of the string $arr_str, and then use the substr () function to intercept the $ARR_STR and intercept to the second-lowest of the $arr_str. This will take the final "," removed.

Usage Experience:

Not recommended, PHP has a more concise and better way to use!

Method Two:

substr ($arr _str, 0,-1)
Detailed: Use the substr () function directly in reverse to cut off the last character;
Use the feeling: still very suitable ~ ~ However, first you have to make sure that the string must have content, and the last one must not!
Method Three:

RTrim ($arr _str, ",")
Explanation: RTrim () function syntax: string RTrim (String $str [, String $character _mask])

Rtrim― Delete whitespace characters (or other characters) at the end of a string

System constant Definition
Go to the thinphp manual to find
echo "<br>". " The root directory address of the Web site ". __root__." ";
echo "<br>". " Portal file Address ". __app__." ";
echo "<br>". " Current module address ". __url__." ";
echo "<br>". " Current URL address ". __self__." ";
echo "<br>". " Current action address ". __action__." ";
echo "<br>". " Template directory for the current module ". __current__." ";
echo "<br>". " The current operation name. Action_name. " ";
echo "<br>". " Current project directory. App_path. " ";
echo "<br>". " The current project name. App_name. " ";
echo "<br>". " The template directory for the current project. App_tmpl_path. " ";
echo "<br>". " The public file directory for the project. App_public_path. " ";
echo "<br>". " The configuration file directory for the project. Config_path. " ";
echo "<br>". " The public file directory for the project. Common_path. " ";
Automatically caches all information related to the table
echo "<br>". " The data file directory for the project. Data_path. "Data directory under Runtime";
echo "<br>". " ". Group_name. "";
echo "<br>". " ". is_cgi.";
echo "<br>". " ". Is_win.";
echo "<br>". " ". Lang_set. "";
echo "<br>". " ". Log_path. "";
echo "<br>". " ". Lang_path. "";
echo "<br>". " ". Tmpl_path. "";
JS put in the location for multiple applications of public resources
echo "<br>". " ". Web_public_path. "";

Three ways to remove the last character of a string in a PHP program