Connection string password with special characters in C#

How to include a password with special characters in the connection string in c#?

If your password contains special characters like $, \, or ;, ensure they are properly escaped.

If your password contains single quotes (') or semicolons (;), it's safer to enclose the entire connection string in double quotes and use single quotes for the password.

For example:

// c# connection string password with special characters
string connectionString = "Server=.;Database=db;User Id=sa;Password='myPa&$w0rd';";

Special characters in passwords typically include \, ;, and " among others.

Use \\ for \, \" for ", and ensure semicolons ; are properly delimited if they appear in the password.

// sql connection string escape character
string connectionString = "Server=.;Database=db;User Id=sa;Password=myPa$$w0rd\"WithQuotes\"";

In the example above, myPa$$w0rd"WithQuotes" is a password containing a dollar sign ($ dollar string c#) and double quotes ("), which are escaped appropriately.

Another example: When connecting to a Dynamics CRM 365 On-Premise instance from an ASP.NET application, you may encounter challenges if the connection account password contains special characters.

For example:

<connectionStrings>
    <add name="CRM365" connectionString="AuthType=AD;Url=http://crm.xxx.com/CRM365; Domain=test; Username=test; Password=T,jL4O&vc%t;30" />
</connectionStrings>

In this example:

• The Password contains special characters like & and ;.
• Directly including these characters in the string causes errors due to XML encoding and connection string parsing rules.

Issues with Special Characters

1. The & character in XML: In XML, the & character must be escaped as &. Failure to do so results in an XML parsing error.

2. The ; character in connection strings: The semicolon (;) is a delimiter in connection strings. To include it as part of the password, you need to wrap the password in either single quotes (') or double quotes (").

You can use single quotes to fix the problem.

Wrap the password in single quotes and escape the & character as &:

<connectionStrings>
    <add name="CRM365" connectionString="AuthType=AD;Url=http://crm.xxx.com/CRM365; Domain=test; Username=test; Password='T,jL4O&amp;vc%t;30'" />
</connectionStrings>

You can also use escaped double quotes to fix the problem.

Alternatively, use double quotes to enclose the password and escape both the & character (&) and the double quotes ("):

<connectionStrings>
    <add name="CRM365" connectionString="AuthType=AD;Url=http://crm.xxx.com/CRM365; Domain=test; Username=test; Password=&quot;T,jL4O&amp;vc%t;30&quot;" />
</connectionStrings>

How to pass a string with special characters in C#?

In the real world, text can include any character.

However, in C#, because strings are enclosed in double quotes, you cannot directly include double quotes within a string.

Attempting to do so will result in a compile-time error.

string text = "This is a "string" in C#.";

To include special characters, C# provides the escaping character \ (backslash).

Use the backslash before special characters, such as double quotes ("), backslash (\), new line (\n), carriage return (\r), tab (\t), etc., to include them in a string.

string text = "This is a \"string\" in C#."; // Escaping double quotes
string str = "xyzdef\rabc";                  // Using carriage return
string path = "\\mypc\\shared\\project";     // Escaping backslashes

By following these guidelines, you can construct and manage connection strings in C# that include passwords with special characters securely and effectively.