CA1056: URI properties should not be strings
Property | Value |
---|---|
Rule ID | CA1056 |
Title | URI properties should not be strings |
Category | Design |
Fix is breaking or non-breaking | Breaking |
Enabled by default in .NET 8 | No |
Cause
A type declares a string property whose name contains "uri", "Uri", "urn", "Urn", "url", or "Url".
By default, this rule only looks at externally visible types, but this is configurable.
Rule description
This rule splits the property name into tokens based on the Pascal casing convention and checks whether each token equals "uri", "Uri", "urn", "Urn", "url", or "Url". If there's a match, the rule assumes that the property represents a uniform resource identifier (URI). A string representation of a URI is prone to parsing and encoding errors, and can lead to security vulnerabilities. The System.Uri class provides these services in a safe and secure manner.
How to fix violations
To fix a violation of this rule, change the property to a Uri type.
When to suppress warnings
It's safe to suppress a warning from this rule if the property doesn't represent a URI.
Suppress a warning
If you just want to suppress a single violation, add preprocessor directives to your source file to disable and then re-enable the rule.
#pragma warning disable CA1056
// The code that's violating the rule is on this line.
#pragma warning restore CA1056
To disable the rule for a file, folder, or project, set its severity to none
in the configuration file.
[*.{cs,vb}]
dotnet_diagnostic.CA1056.severity = none
For more information, see How to suppress code analysis warnings.
Configure code to analyze
Use the following options to configure which parts of your codebase to run this rule on.
- Include specific API surfaces
- Exclude specific symbols
- Exclude specific types and their derived types
You can configure these options for just this rule, for all rules it applies to, or for all rules in this category (Design) that it applies to. For more information, see Code quality rule configuration options.
Include specific API surfaces
You can configure which parts of your codebase to run this rule on, based on their accessibility. For example, to specify that the rule should run only against the non-public API surface, add the following key-value pair to an .editorconfig file in your project:
dotnet_code_quality.CAXXXX.api_surface = private, internal
Exclude specific symbols
You can exclude specific symbols, such as types and methods, from analysis. For example, to specify that the rule should not run on any code within types named MyType
, add the following key-value pair to an .editorconfig file in your project:
dotnet_code_quality.CAXXXX.excluded_symbol_names = MyType
Allowed symbol name formats in the option value (separated by |
):
- Symbol name only (includes all symbols with the name, regardless of the containing type or namespace).
- Fully qualified names in the symbol's documentation ID format. Each symbol name requires a symbol-kind prefix, such as
M:
for methods,T:
for types, andN:
for namespaces. .ctor
for constructors and.cctor
for static constructors.
Examples:
Option Value | Summary |
---|---|
dotnet_code_quality.CAXXXX.excluded_symbol_names = MyType |
Matches all symbols named MyType . |
dotnet_code_quality.CAXXXX.excluded_symbol_names = MyType1|MyType2 |
Matches all symbols named either MyType1 or MyType2 . |
dotnet_code_quality.CAXXXX.excluded_symbol_names = M:NS.MyType.MyMethod(ParamType) |
Matches specific method MyMethod with the specified fully qualified signature. |
dotnet_code_quality.CAXXXX.excluded_symbol_names = M:NS1.MyType1.MyMethod1(ParamType)|M:NS2.MyType2.MyMethod2(ParamType) |
Matches specific methods MyMethod1 and MyMethod2 with the respective fully qualified signatures. |
Exclude specific types and their derived types
You can exclude specific types and their derived types from analysis. For example, to specify that the rule should not run on any methods within types named MyType
and their derived types, add the following key-value pair to an .editorconfig file in your project:
dotnet_code_quality.CAXXXX.excluded_type_names_with_derived_types = MyType
Allowed symbol name formats in the option value (separated by |
):
- Type name only (includes all types with the name, regardless of the containing type or namespace).
- Fully qualified names in the symbol's documentation ID format, with an optional
T:
prefix.
Examples:
Option Value | Summary |
---|---|
dotnet_code_quality.CAXXXX.excluded_type_names_with_derived_types = MyType |
Matches all types named MyType and all of their derived types. |
dotnet_code_quality.CAXXXX.excluded_type_names_with_derived_types = MyType1|MyType2 |
Matches all types named either MyType1 or MyType2 and all of their derived types. |
dotnet_code_quality.CAXXXX.excluded_type_names_with_derived_types = M:NS.MyType |
Matches specific type MyType with given fully qualified name and all of its derived types. |
dotnet_code_quality.CAXXXX.excluded_type_names_with_derived_types = M:NS1.MyType1|M:NS2.MyType2 |
Matches specific types MyType1 and MyType2 with the respective fully qualified names, and all of their derived types. |
Example
The following example shows a type, ErrorProne
, that violates this rule, and a type, SaferWay
, that satisfies the rule.
public class ErrorProne
{
// Violates rule UriPropertiesShouldNotBeStrings.
public string? SomeUri { get; set; }
// Violates rule UriParametersShouldNotBeStrings.
public void AddToHistory(string uriString) { }
// Violates rule UriReturnValuesShouldNotBeStrings.
public string GetRefererUri(string httpHeader)
{
return "http://www.adventure-works.com";
}
}
public class SaferWay
{
// To retrieve a string, call SomeUri.ToString().
// To set using a string, call SomeUri = new Uri(string).
public Uri? SomeUri { get; set; }
public void AddToHistory(string uriString)
{
// Check for UriFormatException.
AddToHistory(new Uri(uriString));
}
public void AddToHistory(Uri uriType) { }
public Uri GetRefererUri(string httpHeader)
{
return new Uri("http://www.adventure-works.com");
}
}
Imports System
Namespace ca1056
Public Class ErrorProne
' Violates rule UriPropertiesShouldNotBeStrings.
Property SomeUri As String
' Violates rule UriParametersShouldNotBeStrings.
Sub AddToHistory(uriString As String)
End Sub
' Violates rule UriReturnValuesShouldNotBeStrings.
Function GetRefererUri(httpHeader As String) As String
Return "http://www.adventure-works.com"
End Function
End Class
Public Class SaferWay
' To retrieve a string, call SomeUri.ToString().
' To set using a string, call SomeUri = New Uri(string).
Property SomeUri As Uri
Sub AddToHistory(uriString As String)
' Check for UriFormatException.
AddToHistory(New Uri(uriString))
End Sub
Sub AddToHistory(uriString As Uri)
End Sub
Function GetRefererUri(httpHeader As String) As Uri
Return New Uri("http://www.adventure-works.com")
End Function
End Class
End Namespace