检查密码包含字母数字和特殊字符

如何检查字符串passwordText是否至少包含

• 1个字母字符
• 1个号码
• 1个特殊字符（符号）

Answer 1

试试这个：

bool result = passwordText.Any(c => char.IsLetter(c)) && passwordText.Any(c => char.IsDigit(c)) && passwordText.Any(c => char.IsSymbol(c)); 

虽然您可能希望通过“字母字符”，“数字”和“符号”更具体地说明您的意思，因为这些术语对不同的人意味着不同的事情，并且您不确定这些术语的定义是否符合定义框架使用。

我猜你用字母表示“az”或“A-Z”，用数字表示“0-9”，用符号表示任何其他可打印的ASCII字符。 如果是这样，试试这个：

 static bool IsLetter(char c) { return (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z'); } static bool IsDigit(char c) { return c >= '0' && c <= '9'; } static bool IsSymbol(char c) { return c > 32 && c < 127 && !IsDigit(c) && !IsLetter(c); } static bool IsValidPassword(string password) { return password.Any(c => IsLetter(c)) && password.Any(c => IsDigit(c)) && password.Any(c => IsSymbol(c)); } 

如果实际上你的意思是别的，那么相应地调整上述方法。

Answer 2

使用RegEx将是最灵活的。 您始终可以将其存储在资源文件中，并在不进行代码更改的情况下进行更改。

有关密码示例，请参阅以下内容

http://regexlib.com/Search.aspx?k=password

Answer 3

您可以使用String.IndexOfAny()来确定字符串中是否存在指定字符数组中的至少一个字符。

Answer 4

 strPassword.IndexOfAny(new char['!','@','#','$','%','^','&','*','(',')']); 

您可以使用您正在寻找的字符/符号数组来运行它。 如果它返回大于-1的任何值，那么你就得到了匹配。 数字也可以这样做。

这将允许您准确定义您要查找的内容，并且如果您愿意，可以轻松地排除某些字符。

Answer 5

这很简单;

 Regex sampleRegex = new Regex(@"(?!^[0-9]*$)(?!^[a-zA-Z]*$)^([a-zA-Z0-9]{2,})$"); boolean isStrongPassword= sampleRegex.IsMatch(givenPassword); 

Answer 6

对于非常简单的事情，我从之前使用的程序中获取了这个。

  //password rules int minUpper = 3; int minLower = 3; int minLength = 8; int maxLength = 12; string allowedSpecials = "@#/.!')"; //entered password string enteredPassword = "TEStpass123@"; //get individual characters char[] characters = enteredPassword.ToCharArray(); //checking variables int upper = 0; int lower = 0; int character = 0; int number = 0; int length = enteredPassword.Length; int illegalCharacters = 0; //check the entered password foreach (char enteredCharacters in characters) { if (char.IsUpper(enteredCharacters)) { upper = upper + 1; } else if (char.IsLower(enteredCharacters)) { lower = lower + 1; } else if (char.IsNumber(enteredCharacters)) { number = number + 1; } else if (allowedSpecials.Contains(enteredCharacters.ToString())) { character = character + 1; } else { illegalCharacters = illegalCharacters + 1; } // MessageBox.Show(chars.ToString()); } if (upper < minUpper || lower < minLower || length < minLength || length > maxLength || illegalCharacters >=1) { MessageBox.Show("Something's not right, your password does not meet the minimum security criteria"); } else { //code to proceed this step } 

Answer 7

这应该符合您的所有要求。 它不使用正则表达式。

 private bool TestPassword(string passwordText, int minimumLength=5, int maximumLength=12,int minimumNumbers=1, int minimumSpecialCharacters=1) { //Assumes that special characters are anything except upper and lower case letters and digits //Assumes that ASCII is being used (not suitable for many languages) int letters = 0; int digits = 0; int specialCharacters = 0; //Make sure there are enough total characters if (passwordText.Length < minimumLength) { ShowError("You must have at least " + minimumLength + " characters in your password."); return false; } //Make sure there are enough total characters if (passwordText.Length > maximumLength) { ShowError("You must have no more than " + maximumLength + " characters in your password."); return false; } foreach (var ch in passwordText) { if (char.IsLetter(ch)) letters++; //increment letters if (char.IsDigit(ch)) digits++; //increment digits //Test for only letters and numbers... if (!((ch > 47 && ch < 58) || (ch > 64 && ch < 91) || (ch > 96 && ch < 123))) { specialCharacters++; } } //Make sure there are enough digits if (digits < minimumNumbers) { ShowError("You must have at least " + minimumNumbers + " numbers in your password."); return false; } //Make sure there are enough special characters -- !(a-zA-Z0-9) if (specialCharacters < minimumSpecialCharacters) { ShowError("You must have at least " + minimumSpecialCharacters + " special characters (like @,$,%,#) in your password."); return false; } return true; } private void ShowError(string errorMessage) { Console.WriteLine(errorMessage); } 

这是如何调用它的示例：

 private void txtPassword_TextChanged(object sender, EventArgs e) { bool temp = TestPassword(txtPassword.Text, 6, 10, 2, 1); } 

这不测试大写和小写字母的混合，这可能是优选的。 为此，只需将char条件中断(ch > 96 && ch < 123)为小写字母组(ch > 64 && ch < 91)为大写。

正则表达式更短更简单（适合那些使用它的人）并且在线有很多例子，但这种方法更适合为用户定制反馈。