datagridview自动求和

[{"title":"（ 20 个子文件 29KB ） datagridview自动求和","children":[{"title":"WindowsApplication1","children":[{"title":"WindowsApplication1","children":[{"title":"bin","children":[{"title":"Debug","children":[{"title":"WindowsApplication1.vshost.exe <span style='color:#111;'> 5.50KB </span>","children":null,"spread":false},{"title":"WindowsApplication1.exe <span style='color:#111;'> 20.00KB </span>","children":null,"spread":false},{"title":"WindowsApplication1.pdb <span style='color:#111;'> 21.50KB </span>","children":null,"spread":false}],"spread":true}],"spread":true},{"title":"obj","children":[{"title":"WindowsApplication1.csproj.FileList.txt <span style='color:#111;'> 305B </span>","children":null,"spread":false},{"title":"Debug","children":[{"title":"WindowsApplication1.csproj.GenerateResource.Cache <span style='color:#111;'> 784B </span>","children":null,"spread":false},{"title":"WindowsApplication1.exe <span style='color:#111;'> 20.00KB </span>","children":null,"spread":false},{"title":"Refactor","children":null,"spread":false},{"title":"WindowsApplication1.Properties.Resources.resources <span style='color:#111;'> 180B </span>","children":null,"spread":false},{"title":"TempPE","children":null,"spread":false},{"title":"WindowsApplication1.pdb <span style='color:#111;'> 21.50KB </span>","children":null,"spread":false}],"spread":true}],"spread":true},{"title":"Properties","children":[{"title":"Resources.Designer.cs <span style='color:#111;'> 2.82KB </span>","children":null,"spread":false},{"title":"Settings.settings <span style='color:#111;'> 249B </span>","children":null,"spread":false},{"title":"Resources.resx <span style='color:#111;'> 5.48KB </span>","children":null,"spread":false},{"title":"Settings.Designer.cs <span style='color:#111;'> 1.08KB </span>","children":null,"spread":false},{"title":"AssemblyInfo.cs <span style='color:#111;'> 1.23KB </span>","children":null,"spread":false}],"spread":true},{"title":"Program.cs <span style='color:#111;'> 478B </span>","children":null,"spread":false},{"title":"WindowsApplication1.csproj <span style='color:#111;'> 3.02KB </span>","children":null,"spread":false},{"title":"WindowsApplication1.csproj.user <span style='color:#111;'> 168B </span>","children":null,"spread":false},{"title":"Form6.Designer.cs <span style='color:#111;'> 4.67KB </span>","children":null,"spread":false},{"title":"Form6.cs <span style='color:#111;'> 1.14KB </span>","children":null,"spread":false}],"spread":true},{"title":"WindowsApplication1.suo <span style='color:#111;'> 13.00KB </span>","children":null,"spread":false},{"title":"WindowsApplication1.sln <span style='color:#111;'> 946B </span>","children":null,"spread":false}],"spread":true}],"spread":true}]