Add readme

Author: BlazorPlus

BlazorDemoKeepPageState.sln

@@ -3,7 +3,12 @@ Microsoft Visual Studio Solution File, Format Version 12.00
 # Visual Studio Version 16
 VisualStudioVersion = 16.0.29920.165
 MinimumVisualStudioVersion = 10.0.40219.1
-Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "BlazorDemoKeepPageState", "BlazorDemoKeepPageState\BlazorDemoKeepPageState.csproj", "{7FB69162-2F7B-4919-8DBF-4921F8FEA59E}"
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "BlazorDemoKeepPageState", "BlazorDemoKeepPageState\BlazorDemoKeepPageState.csproj", "{7FB69162-2F7B-4919-8DBF-4921F8FEA59E}"
+EndProject
+Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "Solution Items", "Solution Items", "{15BFBC42-0B0C-47B6-82C0-376DFECCD2E6}"
+	ProjectSection(SolutionItems) = preProject
+		README.md = README.md
+	EndProjectSection
 EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution

README.md

@@ -0,0 +1,12 @@
+# Blazor Demo Keep Page State
+
+When switch pages , keep state of some pages by code.
+
+In this sampe, 
+
+The state of Index.razor will be persisted until browser reload.
+
+The Counter.razor will be expired in 10 seconds if continue switch to more pages.
+
+
+