开发者

How to check first character of a string if a letter, any letter in C#

开发者 https://www.devze.com 2023-01-13 12:37 出处:网络
I want to take a string and check the first charact开发者_JAVA百科er for being a letter, upper or lower doesn\'t matter, but it shouldn\'t be special, a space, a line break, anything. How can I achiev

I want to take a string and check the first charact开发者_JAVA百科er for being a letter, upper or lower doesn't matter, but it shouldn't be special, a space, a line break, anything. How can I achieve this in C#?


Try the following

string str = ...;
bool isLetter = !String.IsNullOrEmpty(str) && Char.IsLetter(str[0]);


Try the following

bool isValid = char.IsLetter(name.FirstOrDefault());


return (myString[0] >= 'A' && myString[0] <= 'Z') || (myString[0] >= 'a' && myString[0] <= 'z')


You should look up the ASCII table, a table which systematically maps characters to integer values. All lower-case characters are sequential (97-122), as are all upper-case characters (65-90). Knowing this, you do not even have to cast to the int values, just check if the first char of the string is within one of those two ranges (inclusive).

0

精彩评论

暂无评论...
验证码 换一张
取 消