C Sharp getting sub string

C Sharp getting sub string

The question is on C#. I have a string
"value1=1234;value2=2345;value3=3456;value4= ..."
What is the best way to retrieve the values? I only want the values of
"1234", "2345", "3456"... nothing else, and them put them into a list of
strings. How do I solve this? Thanks.