I’m not familiar with ASP.NET. But the regular expression should look like this: ^[a-zA-Z0-9]{6,}$ ^ and $ denote the begin and end of the string respectively; [a-zA-Z0-9] describes one single alphanumeric character and {6,} allows six or more repetitions.
As explained in the rand 0.5.0 docs, gen_ascii_chars is deprecated and you should use sample_iter(&Alphanumeric) instead. use rand::{distributions::Alphanumeric, Rng}; // 0.8 fn main() { let s: String = rand::thread_rng() .sample_iter(&Alphanumeric) .take(7) .map(char::from) .collect(); println!(“{}”, s); }
Write a function that takes a char and returns true if you want to remove that character or false if you want to keep it: bool my_predicate(char c); Then use the std::remove_if algorithm to remove the unwanted characters from the string: std::string s = “my data”; s.erase(std::remove_if(s.begin(), s.end(), my_predicate), s.end()); Depending on your requirements, you … Read more
extension String { var isAlphanumeric: Bool { return !isEmpty && range(of: “[^a-zA-Z0-9]”, options: .regularExpression) == nil } } “”.isAlphanumeric // false “abc”.isAlphanumeric // true “123”.isAlphanumeric // true “ABC123”.isAlphanumeric // true “iOS 9”.isAlphanumeric // false
If you don’t want to bring in a regex library for this one task… NSString *str = @”aA09″; NSCharacterSet *alphaSet = [NSCharacterSet alphanumericCharacterSet]; BOOL valid = [[str stringByTrimmingCharactersInSet:alphaSet] isEqualToString:@””];
Considering you want to check for ASCII Alphanumeric characters, Try this: “^[a-zA-Z0-9]*$”. Use this RegEx in String.matches(Regex), it will return true if the string is alphanumeric, else it will return false. public boolean isAlphaNumeric(String s){ String pattern= “^[a-zA-Z0-9]*$”; return s.matches(pattern); } If it will help, read this for more details about regex: http://www.vogella.com/articles/JavaRegularExpressions/article.html
You’ll want to use the isalpha() and isdigit() standard functions in <ctype.h>. char c=”a”; // or whatever if (isalpha(c)) { puts(“it’s a letter”); } else if (isdigit(c)) { puts(“it’s a digit”); } else { puts(“something else?”); }
How about adding a space in the pattern attribute like pattern=”[a-zA-Z0-9 ]+”. If you want to support any kind of space try pattern=”[a-zA-Z0-9\s]+”
Using MySQL 8.0 or higher Courtesy of michal.jakubeczy’s answer below, replacing by Regex is now supported by MySQL: UPDATE {table} SET {column} = REGEXP_REPLACE({column}, ‘[^0-9a-zA-Z ]’, ”) Using MySQL 5.7 or lower Regex isn’t supported here. I had to create my own function called alphanum which stripped the chars for me: DROP FUNCTION IF EXISTS … Read more