added isnumber

Author: ildoc

src/Extensions/ObjectExtensions.cs

@@ -0,0 +1,20 @@
+namespace Extensions
+{
+    public static class ObjectExtensions
+    {
+        public static bool IsNumber(this object value)
+        {
+            return value is sbyte
+                    || value is byte
+                    || value is short
+                    || value is ushort
+                    || value is int
+                    || value is uint
+                    || value is long
+                    || value is ulong
+                    || value is float
+                    || value is double
+                    || value is decimal;
+        }
+    }
+}

tests/Extensions.Tests/DateTimeExtensionsTests.cs

@@ -30,4 +30,20 @@ public void ShouldCalculateAgeOnSpecificDate()
             birthday.ToAgeAtDate(new DateTime(2022, 4, 12)).Should().Be(31);
         }
     }
+
+    public class ObjectExtensionsTests
+    {
+        [Theory]
+        [InlineData(false, false)]
+        [InlineData(null, false)]
+        [InlineData("lallallero", false)]
+        [InlineData(123, true)]
+        [InlineData(1.3, true)]
+        [InlineData(-123, true)]
+        [InlineData(-1.3, true)]
+        public void ShouldCheckIfNumber(object o, bool expected)
+        {
+            o.IsNumber().Should().Be(expected);
+        }
+    }
 }