如何从逗号分隔的显示名称和电子邮件地址检查电子邮件地址是否有效......
"a1 b.d"<a1@test.com>, // this is valid
<a2@test.com>, // this is valid
"a3 b.d"<a3@test.com> , // this is valid
a b.c a4@test.com , // this is not valid
"a1 b.d"<a1@test.com>, // this is valid
<a2test.com>, // this is not valid
"a3 b.d"<a3@testcom> , // this is not valid
" a b.c a4@test.com " , // this is not valid
如果整体有效吗?怎么检查?