Multiline string in Azure Pipelines - yaml

Question

Can I use a multiline YAML string in Azure Pipelines?
Using the ASP.NET Core (.NET Framework) template I tried multilining the msbuildArgs but that didn't work.
- task: VSBuild#1
inputs:
solution: '$(solution)'
msbuildArgs: >
'/p:DeployOnBuild=true /p:WebPublishMethod=Package'
'/p:PackageAsSingleFile=true /p:SkipInvalidConfigurations=true'
'/p:DesktopBuildPackageLocation="$(build.artifactStagingDirectory)\WebApp.zip"'
'/p:DeployIisAppPath="Default Web Site"'
platform: '$(buildPlatform)'
configuration: '$(buildConfiguration)'
MSBUILD : error MSB1008: Only one project can be specified.
Switch: '/p:DeployOnBuild=true
Reviewing the string reference documentation I don't see any about this topic.

Answer 1

I always use the YAML block chomping operator like this
msbuildArgs: >-
/p:DeployOnBuild=true
/p:WebPublishMethod=Package
/p:PackageAsSingleFile=true
/p:SkipInvalidConfigurations=true
/p:DesktopBuildPackageLocation="$(build.artifactStagingDirectory)\WebApp.zip"
/p:DeployIisAppPath="Default Web Site"
Works well and makes things crystal clear and neat

Answer 2

You can just put ' in the start and the end of the msbuildArgs:
- task: VSBuild#1
displayName: 'Build solution **\*.sln'
inputs:
vsVersion: latest
msbuildArgs: '/p:DeployOnBuild=true /p:WebPublishMethod=Package
/p:PackageAsSingleFile=true /p:SkipInvalidConfigurations=true'

Answer 3

Multiline string in Azure Pipelines
Shayki Abramczyk pointed out the key to the this error.
Just put one ' in the start and the end of the msbuildArgs
without having to configure for each MSBuild argument
As test, following YAML work for me:
- task: VSBuild#1
displayName: 'Build solution YourSolution'
inputs:
solution: $(solution)
msbuildArgs: '/p:DeployOnBuild=true /p:WebPublishMethod=Package /p:PackageAsSingleFile=true /p:SkipInvalidConfigurations=true /p:DesktopBuildPackageLocation="$(build.artifactStagingDirectory)\WebApp.zip" /p:DeployIisAppPath="Default Web Site"'
platform: '$(buildPlatform)'
configuration: '$(buildConfiguration)'
Note: The variable $(solution) should point to a specific solution .sln or project .csproj file instead of **\*.sln. If you have one more solution in your repo, you may get the error Only one project can be specified.
Update:
but I don’t want super long run-on line as in your answer provided. I
want to split across multiple lines!
If you do not want to super long run-on line as in MSBuild arguments, you could split them directly, but pay attention to indentation, like:
- task: VSBuild#1
displayName: 'Build solution YourSolution'
inputs:
solution: $(solution)
msbuildArgs: '/p:DeployOnBuild=true
/p:WebPublishMethod=Package
/p:PackageAsSingleFile=true
/p:SkipInvalidConfigurations=true
/p:DesktopBuildPackageLocation="$(build.artifactStagingDirectory)\WebApp.zip"
/p:DeployIisAppPath="Default Web Site"'
platform: '$(buildPlatform)'
configuration: '$(buildConfiguration)'
As test, it works fine.
Hope this helps.