正则表达式检查句子中仅包含字母的两个单词

Question

This checks for two words but also returns true if words contains numbers. So, How can I to check for two words containing only letters in a sentence with this Regex?

Regex.IsMatch(alphabets, @"^((?:\S+\s+){2}\S+).*");
//should return true if string is Honda Civic
//should return false if string is Honda Civic TypeR
//should return false if string is H56da Civic 
//should return false if string is Honda

Answer 1

You can use

^[A-Z][a-z]+\s+[A-Z][a-z]+$

• ^ Start of string
• [AZ][az]+\s+ Match an uppercase char AZ, 1+ lowercase chars az and 1+ whitespace chars
• [AZ][az]+ Match an uppercase char AZ and 1+ lowercase chars az
• $ End of string

Regex demo

Or a bit broader, where \p{Lu} matches an uppercase letter that has a lowercase variant, p{Ll} matches a lowercase letter that has an uppercase variant and [\p{Zs}\t] matches a whitespace char or a tab.

^\p{Lu}\p{Ll}+[\p{Zs}\t]+\p{Lu}\p{Ll}+$

Example

string[] strings = { 
    "Honda Civic",
    "Civic TypeR",
    "H56da Civic",
    "Honda"
    };
foreach (String alphabets in strings) {
    Console.WriteLine(Regex.IsMatch(alphabets, @"^[A-Z][a-z]+\s+[A-Z][a-z]+$"));
}

Output

True
False
False
False