环境：
Centos7
.Net core 2.0
问题：
使用QRCoder 报“Unable to load DLL 'gdiplus'"
同 https://q.cnblogs.com/q/98966/
解决：
yum install libgdiplus-devel
注意：
yum install libgdiplus 后，在centos7 下，程序并不能运行成功还是报错，查看libgdiplus安装情况
rpm -qa |grep libgdiplus
rpm -ql libgdiplus-2.10-9.el7.x86_64
在/usr/lib64下缺少libgdiplus.so文件
Centos7 需要通过安装libgdiplus-devel来解决
参考文章：
https://q.cnblogs.com/q/98966/
https://github.com/CoreCompat/System.Drawing/issues/8
If I recall correctly, the .so file for libgdiplus is named libgdiplus.so. on CentOS (see https://centos.pkgs.org/7/epel-x86_64/libgdiplus-2.10-9.el7.x86_64.rpm.html). CoreCompat.System.Drawing is looking for libgdiplus.so so that doesn't work. On CentOS, you need to install the libgdiplus-devel package.