How pass string separated by spaces parameter to Jenkins build trigger?
You just need to replace the blank space by %20 :
http://JENKINS_SERVER/job/YOUR_JOB_NAM/buildWithParameters?myparam=Hello%20world
This is known as Url Enconding used for unsafe or special characters.
This is a summary table :
character encoded equivalencebackspace %08tab %09space %20! %21" %22# %23$ %24% %25& %26' %27( %28) %29* %2A+ %2B, %2C- %2D. %2E/ %2F: %3A; %3B< %3C= %3D> %3E? %3F@ %40[ %5B\ %5C] %5D^ %5E_ %5F` %60{ %7B| %7C} %7D¿ %BF
References: