1 files changed, 37 insertions, 0 deletions
diff --git a/tools/Check-DotNetSdk.ps1 b/tools/Check-DotNetSdk.ps1
new file mode 100644
index 00000000..6c9fa772
--- /dev/null
+++ b/tools/Check-DotNetSdk.ps1
@@ -0,0 +1,37 @@
+<#
+.SYNOPSIS
+    Checks whether the .NET Core SDK required by this repo is installed.
+#>
+[CmdletBinding()]
+Param (
+)
+
+$dotnet = Get-Command dotnet -ErrorAction SilentlyContinue
+if (!$dotnet) {
+    # Nothing is installed.
+    Write-Output $false
+    exit 1
+}
+
+# We need to set the current directory so dotnet considers the SDK required by our global.json file.
+Push-Location "$PSScriptRoot\.."
+try {
+    dotnet -h 2>&1 | Out-Null
+    if (($LASTEXITCODE -eq 129) -or      # On Linux
+        ($LASTEXITCODE -eq -2147450751)  # On Windows
+        ) {
+        # These exit codes indicate no matching SDK exists.
+        Write-Output $false
+        exit 2
+    }
+
+    # The required SDK is already installed!
+    Write-Output $true
+    exit 0
+} catch {
+    # I don't know why, but on some build agents (e.g. MicroBuild), an exception is thrown from the `dotnet` invocation when a match is not found.
+    Write-Output $false
+    exit 3
+} finally {
+    Pop-Location
+}