cd 进入qt creator 的bin 文件夹
cmd
C:\Qt\qtcreator421\bin>set QT_SCALE_FACTOR=1
C:\Qt\qtcreator421\bin>echo %QT_SCALE_FACTOR%
1
C:\Qt\qtcreator421\bin>qtcreator.exe
cd 进入qt creator 的bin 文件夹
cmd
C:\Qt\qtcreator421\bin>set QT_SCALE_FACTOR=1
C:\Qt\qtcreator421\bin>echo %QT_SCALE_FACTOR%
1
C:\Qt\qtcreator421\bin>qtcreator.exe