问题
Months ago I made a short code that uses mb_strimwidth() to exactly fit some text into a table cell, putting dots at the end of a truncated string.
Now, after some times, I tried to execute that same code and it went out with this error:
Fatal error: Call to undefined function mb_strimwidth() in ...
I tried to find the mbstring.php file, and when I found the mb_strimwidth() function, I discovered that it is not implemented anymore. How is that possible?
But my main question is: how can I get the same result as mb_strimwidth()?
I thought to rewrite the function using a loop and mb_strwidth(), but ALL the functions in that mbstring.php file are empty.
回答1:
All mb_* functions are provided by a PHP extension called Multibyte String, internal name mbstring
You probably don't have the extension active or installed. On most Linux distros you can install the package php-mbstring to install and activate this extension.
Apache needs to be restarted afterwards if you are using mod_php
回答2:
Just got this issue, if you are using linux just install the package php-mbstringand restart Apache.
sudo apt-get install php-mbstring
sudo service apache2 restart
回答3:
u need to install php-mbstring package try.
check php version
php -v
then check mbstring already install and enable
php -i | grep mbstring
if not installed run this command
sudo apt-get install php-mbstring
if you are php other version example : 7.1, 7.2, 7.0 based on run command like this :
sudo apt-get install php7.1-mbstring
if you are using nginx server for run laravel .. then check nginx configration file which version u have loaded in conf file..
go to cd /etc/nginx/sites-available and open your configuration file..
if you are loading php7.2 version in nginx conf file..
fastcgi_pass unix:/var/run/php/php7.1-fpm.sock;
then u need to install 7.2 mbstring package..
sudo apt-get install php7.2-mbstring
and restart apache2 server
sudo service apache2 restart
回答4:
if you already installed mbstring then you have to call this extension on php.ini file.
First, detect where is your php-fpm.ini file or php.ini.
run command
php -i | grep php.ini
it returns you path of php.ini file.
for example
/etc/php.ini
then open file with VIM or another editor
vim /etc/php.ini
and then add mbstring extension to php.ini file
extension=mbstring.so;
finally, restart php-fpm
systemctl restart php-fpm
来源：https://stackoverflow.com/questions/14254943/call-to-undefined-function-mb-strimwidth