add SqlParameter default Ctor

Author: Ahoo-Wang

build/version.props

@@ -2,7 +2,7 @@
 	<PropertyGroup>
 		<VersionMajor>4</VersionMajor>
 		<VersionMinor>0</VersionMinor>
-		<VersionPatch>8</VersionPatch>
+		<VersionPatch>10</VersionPatch>
 		<VersionPrefix>$(VersionMajor).$(VersionMinor).$(VersionPatch)</VersionPrefix>
 	</PropertyGroup>
 </Project>

src/SmartSql.Test.Unit/DbSessions/DbSessionTest.cs

@@ -235,8 +235,9 @@ public void DeleteCheckIsNotEmptyRequired()
         public void SP()
         {
             SqlParameterCollection dbParameterCollection = new SqlParameterCollection();
-            dbParameterCollection.Add(new SqlParameter("Total",null,typeof(int))
+            dbParameterCollection.Add(new SqlParameter
             {
+                Name = "Total",
                 DbType = System.Data.DbType.Int32,
                 Direction = System.Data.ParameterDirection.Output
             });

src/SmartSql/Data/SqlParameter.cs

@@ -10,14 +10,38 @@ namespace SmartSql.Data
     public class SqlParameter
     {
         private DbParameter _sourceParameter;
+        private object _value;
+        public SqlParameter()
+        {
+        }
+        public SqlParameter(string name, object val)
+        {
+            Name = name;
+            Value = val;
+            if (val != null)
+            {
+                ParameterType = val.GetType();
+            }
+        }
         public SqlParameter(string name, object val, Type parameterType)
         {
             Name = name;
             Value = val;
             ParameterType = parameterType;
         }
         public string Name { get; set; }
-        public object Value { get; set; }
+        public object Value
+        {
+            get => _value;
+            set
+            {
+                _value = value;
+                if (value != null)
+                {
+                    ParameterType = value.GetType();
+                }
+            }
+        }
         public Type ParameterType { get; set; }
         public Action<SqlParameter> OnSetSourceParameter { get; set; }