pictiuebox效率低，这里使用高效重绘方法，vs2017，代码很短，鼠标判断等就200行，只使用了panel 实现。
可添加多个图像元素，移动元素并调整元素图层。
资源文件列表
Demo_1/.vs/Demo_1/v15/.suo , 33280
Demo_1/.vs/Demo_1/v15/Server/sqlite3/db.lock , 0
Demo_1/.vs/Demo_1/v15/Server/sqlite3/storage.ide , 585728
Demo_1/.vs/Demo_1/v15/Server/sqlite3/storage.ide-shm , 32768
Demo_1/.vs/Demo_1/v15/Server/sqlite3/storage.ide-wal , 4128272
Demo_1/Demo_1/App.config , 189
Demo_1/Demo_1/bin/Debug/01.jpg , 53060
Demo_1/Demo_1/bin/Debug/02.png , 107092
Demo_1/Demo_1/bin/Debug/back.jpg , 279992
Demo_1/Demo_1/bin/Debug/Demo_1.exe , 12800
Demo_1/Demo_1/bin/Debug/Demo_1.exe.config , 189
Demo_1/Demo_1/bin/Debug/Demo_1.pdb , 36352
Demo_1/Demo_1/Demo_1.csproj , 3483
Demo_1/Demo_1/Form1.cs , 8508
Demo_1/Demo_1/Form1.Designer.cs , 1228
Demo_1/Demo_1/obj/Debug/Demo_1.csproj.CoreCompileInputs.cache , 42
Demo_1/Demo_1/obj/Debug/Demo_1.csproj.FileListAbsolute.txt , 399
Demo_1/Demo_1/obj/Debug/Demo_1.csproj.GenerateResource.cache , 954
Demo_1/Demo_1/obj/Debug/Demo_1.exe , 12800
Demo_1/Demo_1/obj/Debug/Demo_1.pdb , 36352
Demo_1/Demo_1/obj/Debug/Demo_1.Properties.Resources.resources , 180
Demo_1/Demo_1/obj/Debug/DesignTimeResolveAssemblyReferences.cache , 831
Demo_1/Demo_1/obj/Debug/DesignTimeResolveAssemblyReferencesInput.cache , 7064
Demo_1/Demo_1/obj/Debug/TemporaryGeneratedFile_036C0B5B-1481-4323-8D20-8F5ADCB23D92.cs , 0
Demo_1/Demo_1/obj/Debug/TemporaryGeneratedFile_5937a670-0e60-4077-877b-f7221da3dda1.cs , 0
Demo_1/Demo_1/obj/Debug/TemporaryGeneratedFile_E7A71F73-0F8D-4B9B-B56E-8E70B10BC5D3.cs , 0
Demo_1/Demo_1/Program.cs , 518
Demo_1/Demo_1/Properties/AssemblyInfo.cs , 1310
Demo_1/Demo_1/Properties/Resources.Designer.cs , 2825
Demo_1/Demo_1/Properties/Resources.resx , 5612
Demo_1/Demo_1/Properties/Settings.Designer.cs , 1093
Demo_1/Demo_1/Properties/Settings.settings , 249
Demo_1/Demo_1.sln , 1116