$re = '/(^Project\("{[a-f0-9]{8}-[a-f0-9]{4}-[a-f0-9]{4}-[a-f0-9]{4}-[a-f0-9]{12}}"\)\s*=\s*"[\w\d-.]*"\s*,\s*")\K([\w\d-.\\\\\s]*)(?=".*$)/mi';
$str = 'Microsoft Visual Studio Solution File, Format Version 12.00
# Visual Studio 14
VisualStudioVersion = 14.0.25420.1
MinimumVisualStudioVersion = 10.0.40219.1
Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "CCH.WFM.UnitTest.Framework", "Source\\Common\\Tests\\Unit Tests\\WFMTestFramework\\CCH.WFM.UnitTest.Framework.csproj", "{044E36A5-189E-45B1-9753-397BC8ACD31A}"
EndProject
Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "CCH.WFM.ServiceTest", "Source\\Common\\Tests\\Unit Tests\\ServiceTest\\CCH.WFM.ServiceTest.csproj", "{94E3C16B-DFBA-403A-95F9-37FAB7AB88ED}"
EndProject
Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "TestFramework", "..\\test\\TestFramework\\TestFramework.csproj", "{3F56B03C-0883-4705-91BA-0979CAF6E719}"
EndProject
Global
GlobalSection(SolutionConfigurationPlatforms) = preSolution
Debug|Any CPU = Debug|Any CPU
Release|Any CPU = Release|Any CPU
EndGlobalSection
GlobalSection(ProjectConfigurationPlatforms) = postSolution
{044E36A5-189E-45B1-9753-397BC8ACD31A}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
{044E36A5-189E-45B1-9753-397BC8ACD31A}.Debug|Any CPU.Build.0 = Debug|Any CPU
{044E36A5-189E-45B1-9753-397BC8ACD31A}.Release|Any CPU.ActiveCfg = Release|Any CPU
{044E36A5-189E-45B1-9753-397BC8ACD31A}.Release|Any CPU.Build.0 = Release|Any CPU
{94E3C16B-DFBA-403A-95F9-37FAB7AB88ED}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
{94E3C16B-DFBA-403A-95F9-37FAB7AB88ED}.Debug|Any CPU.Build.0 = Debug|Any CPU
{94E3C16B-DFBA-403A-95F9-37FAB7AB88ED}.Release|Any CPU.ActiveCfg = Release|Any CPU
{94E3C16B-DFBA-403A-95F9-37FAB7AB88ED}.Release|Any CPU.Build.0 = Release|Any CPU
{3F56B03C-0883-4705-91BA-0979CAF6E719}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
{3F56B03C-0883-4705-91BA-0979CAF6E719}.Debug|Any CPU.Build.0 = Debug|Any CPU
{3F56B03C-0883-4705-91BA-0979CAF6E719}.Release|Any CPU.ActiveCfg = Release|Any CPU
{3F56B03C-0883-4705-91BA-0979CAF6E719}.Release|Any CPU.Build.0 = Release|Any CPU
EndGlobalSection
GlobalSection(SolutionProperties) = preSolution
HideSolutionNode = FALSE
EndGlobalSection
GlobalSection(TeamFoundationVersionControl) = preSolution
SccNumberOfProjects = 4
SccEnterpriseProvider = {4CA58AB2-18FA-4F8D-95D4-32DDF27D184C}
SccTeamFoundationServer = https://tfs2013.prosystemfx.com/tfs/nextgen
SccLocalPath0 = .
SccProjectUniqueName1 = Source\\\\Common\\\\Tests\\\\Unit\\u0020Tests\\\\WFMTestFramework\\\\CCH.WFM.UnitTest.Framework.csproj
SccProjectName1 = Source/Common/Tests/Unit\\u0020Tests/WFMTestFramework
SccLocalPath1 = Source\\\\Common\\\\Tests\\\\Unit\\u0020Tests\\\\WFMTestFramework
SccProjectUniqueName2 = Source\\\\Common\\\\Tests\\\\Unit\\u0020Tests\\\\ServiceTest\\\\CCH.WFM.ServiceTest.csproj
SccProjectName2 = Source/Common/Tests/Unit\\u0020Tests/ServiceTest
SccLocalPath2 = Source\\\\Common\\\\Tests\\\\Unit\\u0020Tests\\\\ServiceTest
SccProjectUniqueName3 = ..\\\\test\\\\TestFramework\\\\TestFramework.csproj
SccProjectName3 = ../test/TestFramework
SccLocalPath3 = ..\\\\test\\\\TestFramework
EndGlobalSection
EndGlobal
';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php