Lin , I don't think we chinese say 'ni hao ma?' as a greeting sentence. we usually say 'ni hao!' ,don't we?

chinese ask others "have you finished your breakfast/lunch/supper" as american talk about "what a fine day",so if you meet someday nearly a meal time,you can say this

hen gao xing ren shi ni 很高兴认识你 = nice to meet you (literally means, nice to know you)

nice to meet you=很高兴见到你（hen gao xing jian dao ni)

how are you？=你好吗？（ni hao ma)