iOS nsstring 截取字符前后字符串
// Str = @"PEK_LHR"
NSRange range = [trafficeStr rangeOfString:@"_" options:NSBackwardsSearch];
from = [trafficeStr substringToIndex:range.location];
to = [trafficeStr substringFromIndex:range.location + 1];
// Str = @"PEK_LHR"
NSRange range = [trafficeStr rangeOfString:@"_" options:NSBackwardsSearch];
from = [trafficeStr substringToIndex:range.location];
to = [trafficeStr substringFromIndex:range.location + 1];