How edit or add properties in inline task - msbuild

Question

I need invoke msbuild task with properties, whats name can be calculated only in runtime. I try do it by this scripts
Main.xml
<?xml version="1.0" encoding="utf-8"?>
<Project xmlns="http://schemas.microsoft.com/developer/msbuild/2003" ToolsVersion="14.0" DefaultTargets="Build">
<UsingTask TaskName="GetVars" TaskFactory="CodeTaskFactory" AssemblyFile="$(MSBuildToolsPath)\Microsoft.Build.Tasks.v4.0.dll">
<ParameterGroup>
<Result ParameterType="System.String" Output="true"/>
</ParameterGroup>
<Task>
<Code Type="Fragment" Language="cs">
<![CDATA[
this.Result = "AAA=123;BBB=456;";
]]>
</Code>
</Task>
</UsingTask>
<PropertyGroup>
<Vars></Vars>
</PropertyGroup>
<Target Name="Make">
<GetVars>
<Output TaskParameter="Result" PropertyName="Vars"/>
</GetVars>
<MSBuild Projects="Proj.xml" Targets="make" Properties="$(Vars)"/>
</Target>
</Project>
Proj.xml
<?xml version="1.0" encoding="utf-8"?>
<Project xmlns="http://schemas.microsoft.com/developer/msbuild/2003" DefaultTargets="Build">
<Target Name="Make">
<Message Text="AAA = $(AAA)"/>
<Message Text="BBB = $(BBB)"/>
</Target>
</Project>
This script give this output:
AAA = 123;BBB=456;
BBB =
I expected this output:
AAA = 123;
BBB = 456;

Answer 1

If you want the inline task to produce several items (the msbuild equivalent of an array or list in other languages), you should state it like that instead of using a property (which is a single key/value pair). This is covered in some of the Inline Task documentation - however that uses full-blown ITaskItems whereas just using a String array will do. So:
output a System.String[] from the inline task
assign it to an Item instead of Property using ItemName =
pass the Item to the MSbuild task (which is what it expects anyway), using #() notation
In code:
<?xml version="1.0" encoding="utf-8"?>
<Project xmlns="http://schemas.microsoft.com/developer/msbuild/2003" ToolsVersion="14.0" DefaultTargets="Make">
<UsingTask TaskName="GetVars" TaskFactory="CodeTaskFactory" AssemblyFile="$(MSBuildToolsPath)\Microsoft.Build.Tasks.v4.0.dll">
<ParameterGroup>
<Result ParameterType="System.String[]" Output="true"/>
</ParameterGroup>
<Task>
<Code Type="Fragment" Language="cs">
<![CDATA[
this.Result = new System.String[]{"AAA=123", "BBB=456"};
]]>
</Code>
</Task>
</UsingTask>
<Target Name="Make">
<GetVars>
<Output TaskParameter="Result" ItemName="Vars"/>
</GetVars>
<MSBuild Projects="$(MSBuildThisFile)" Targets="Show" Properties="#(Vars)"/>
</Target>
<Target Name="Show">
<Message Text="AAA = $(AAA)"/>
<Message Text="BBB = $(BBB)"/>
</Target>
</Project>
Output:
Show:
AAA = 123
BBB = 456