Enforces an int operand on bitwise and shift operations
Cette page n'est pas encore disponible en français, sa traduction est en cours.
Si vous avez des questions ou des retours sur notre projet de traduction actuel,
n'hésitez pas à nous contacter.
ID: csharp-best-practices/bitwise-right-operand-int
Language: C#
Severity: Error
Category: Error Prone
Description
When a variable is marked dynamic, the compiler does not validate that the right operand of bitwise or shift operations is valid, which can lead to an unexpected run-time exception. This rule checks that the right operand of bitwise and shift operations is of type int, sbyte, byte, short, ushort, or char.
Input:
dynamic dyn = 4;
// The next line causes a run-time exception:
var shifted = dyn << 2.0;
Output:
Run-time exception (line 6): Operator '<<' cannot be applied to operands of type 'int' and 'double'\
Stack Trace:\
[Microsoft.CSharp.RuntimeBinder.RuntimeBinderException: Operator '<<' cannot be applied to operands of type 'int' and 'double']\
at CallSite.Target(Closure , CallSite , Object , Double )\
at System.Dynamic.UpdateDelegates.UpdateAndExecute2[T0,T1,TRet](CallSite site, T0 arg0, T1 arg1)\
at Program.Main()
Non-Compliant Code Examples
class NonCompliant {
public static void Main()
{
dynamic dyn = 4;
var binExp = dyn << 1;
binExpr = dyn << new { amount = 1 };
binExpr = dyn << new int[1];
binExpr = dyn << (double)2;
binExpr = dyn << default(double);
binExpr = dyn << new[]{1};
binExpr = dyn << new("key", "value");
binExpr = dyn << {["key"] = 4};
binExpr = dyn << $"{2}";
binExpr = dyn << 1..2;
binExpr = dyn << typeof(int);
binExpr = dyn << 2.0;
binExpr = dyn << null;
binExpr = dyn << true;
binExpr = dyn << "2";
binExpr = dyn << @"2";
binExpr = dyn << """2""";
binExpr = dyn << 2F;
binExpr = dyn << 2f;
binExpr = dyn << 2L;
binExpr = dyn << 2l;
binExpr = dyn << 2U;
binExpr = dyn << 2u;
binExpr = dyn << 2UL;
binExpr = dyn << 2ul;
binExpr = dyn << 2M;
binExpr = dyn << 2m;
binExpr = dyn << 2E+1;
binExpr = dyn << 2e+1;
binExpr = dyn << (1, 2);
binExpr = dyn << new object();
var assignment = dyn << 1;
assignment <<= new { amount = 1 };
assignment <<= new int[1];
assignment <<= (double)2;
assignment <<= default(object);
assignment <<= new[]{1};
assignment <<= new("key", "value");
assignment <<= {["key"] = 4};
assignment <<= $"{2}";
assignment <<= 1..2;
assignment <<= typeof(int);
assignment <<= 2.0;
assignment <<= null;
assignment <<= true;
assignment <<= "2";
assignment <<= @"2";
assignment <<= """2""";
assignment <<= 2F;
assignment <<= 2f;
assignment <<= 2L;
assignment <<= 2l;
assignment <<= 2U;
assignment <<= 2u;
assignment <<= 2UL;
assignment <<= 2ul;
assignment <<= 2M;
assignment <<= 2m;
assignment <<= 2E+1;
assignment <<= 2e+1;
assignment <<= (1, 2);
assignment <<= new object();
}
}
Compliant Code Examples
class Compliant {
public static void Main()
{
dynamic dyn = 4;
var binExp = dyn << 1;
binExp = dyn << (int)2.1;
binExp = dyn << (byte)2.1;
binExp = dyn << (short)2.1;
binExp = dyn << (ushort)2.1;
binExp = dyn << (char)2.1;
binExp = dyn << default(int);
binExp = dyn << 2;
binExp = dyn << 0b0000010;
binExp = dyn << 0x2;
binExp = dyn << '2';
var assignment = dyn << 1;
assignment <<= (int)2.1;
assignment <<= (sbyte)2.1;
assignment <<= (byte)2.1;
assignment <<= (short)2.1;
assignment <<= (ushort)2.1;
assignment <<= (char)2.1;
assignment <<= default(int);
assignment <<= 2;
assignment <<= 0b0000010;
assignment <<= 0x2;
assignment <<= '2';
myObject = new MyObject(123);
}
}
