BuildDeploymentManifestInputProject Property MSBuild Extension Pack Help 4.0.12.0
Each .dtproj is a separate item in an ItemGroup, but each item needs a custom OutputDirectory metadata value that specifies where the deployment manifest should be written and project files copied to

Namespace: MSBuild.ExtensionPack.SqlServer
Assembly: MSBuild.ExtensionPack (in MSBuild.ExtensionPack.dll) Version: 4.0.0.0
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