where U

Dapper.Lite/Dapper.Lite/SqlString/ISqlString.cs

@@ -21,6 +21,12 @@ namespace Dapper.Lite
         /// </summary>
         /// <param name="expression">Lambda 表达式</param>
         ISqlString<T> Where(Expression<Func<T, object>> expression);
+
+        /// <summary>
+        /// 追加参数化查询条件SQL
+        /// </summary>
+        /// <param name="expression">Lambda 表达式</param>
+        ISqlString<T> Where<U>(Expression<Func<U, object>> expression);
         #endregion
 
     }

Dapper.Lite/Dapper.Lite/SqlString/SqlString.cs

@@ -66,6 +66,43 @@ namespace Dapper.Lite
         }
         #endregion
 
+        #region Where
+        /// <summary>
+        /// 追加参数化查询条件SQL
+        /// </summary>
+        /// <param name="expression">Lambda 表达式</param>
+        public ISqlString<T> Where<U>(Expression<Func<U, object>> expression)
+        {
+            try
+            {
+                ExpressionHelper<U> condition = new ExpressionHelper<U>(_provider, DbParameterNames, SqlStringMethod.Where);
+
+                DbParameter[] dbParameters;
+                string result = condition.VisitLambda(expression, out dbParameters);
+
+                if (dbParameters != null)
+                {
+                    result = ParamsAddRange(dbParameters, result);
+                }
+
+                if (Sql.ToString().Contains(" where "))
+                {
+                    Sql.Append(" and " + result);
+                }
+                else
+                {
+                    Sql.Append(" where " + result);
+                }
+            }
+            catch
+            {
+                throw;
+            }
+
+            return this;
+        }
+        #endregion
+
     }
 
     /// <summary>

Dapper.Lite/Dapper.Lite/Utils/ExpressionHelper.cs

@@ -353,6 +353,49 @@ namespace Dapper.Lite
         }
         #endregion
 
+        #region VisitMember 字段或属性
+        /// <summary>
+        /// 字段或属性
+        /// </summary>
+        public ExpMemberValue VisitMember(Expression exp, MemberExpression parent = null)
+        {
+            ExpMemberValue result = new ExpMemberValue();
+
+            if (exp.NodeType == ExpressionType.MemberAccess)
+            {
+                MemberExpression mebmerExp = exp as MemberExpression;
+                if (mebmerExp.Expression is ParameterExpression) // 例: exp = t.Remark
+                {
+                    ParameterExpression parameterExp = mebmerExp.Expression as ParameterExpression;
+
+                    result.MemberParentName = parameterExp.Name;
+                    result.MemberDBField = GetDbField(mebmerExp.Member.Name, mebmerExp.Expression.Type);
+                    result.MemberName = mebmerExp.Member.Name;
+                    result.MemberAliasName = mebmerExp.Member.Name;
+
+                    if (Alias == null && mebmerExp.Expression.Type == typeof(T))
+                    {
+                        Alias = parameterExp.Name;
+                    }
+                }
+                else
+                {
+                    throw new Exception("不支持");
+                }
+            }
+            else if (exp.NodeType == ExpressionType.Convert) //例：exp = t.OrderTime >= startTime (表达式左边OrderTime的类型是可空类型DateTime?)
+            {
+                return VisitMember((exp as UnaryExpression).Operand);
+            }
+            else
+            {
+                throw new Exception("不支持");
+            }
+
+            return result;
+        }
+        #endregion
+
         #region VisitValue 取值
         /// <summary>
         /// 第一级
@@ -398,49 +441,6 @@ namespace Dapper.Lite
         }
         #endregion
 
-        #region VisitMember 字段或属性
-        /// <summary>
-        /// 字段或属性
-        /// </summary>
-        public ExpMemberValue VisitMember(Expression exp, MemberExpression parent = null)
-        {
-            ExpMemberValue result = new ExpMemberValue();
-
-            if (exp.NodeType == ExpressionType.MemberAccess)
-            {
-                MemberExpression mebmerExp = exp as MemberExpression;
-                if (mebmerExp.Expression is ParameterExpression) // 例: exp = t.Remark
-                {
-                    ParameterExpression parameterExp = mebmerExp.Expression as ParameterExpression;
-
-                    result.MemberParentName = parameterExp.Name;
-                    result.MemberDBField = GetDbField(mebmerExp.Member.Name, mebmerExp.Expression.Type);
-                    result.MemberName = mebmerExp.Member.Name;
-                    result.MemberAliasName = mebmerExp.Member.Name;
-
-                    if (Alias == null && mebmerExp.Expression.Type == typeof(T))
-                    {
-                        Alias = parameterExp.Name;
-                    }
-                }
-                else
-                {
-                    throw new Exception("不支持");
-                }
-            }
-            else if (exp.NodeType == ExpressionType.Convert) //例：exp = t.OrderTime >= startTime (表达式左边OrderTime的类型是可空类型DateTime?)
-            {
-                return VisitMember((exp as UnaryExpression).Operand);
-            }
-            else
-            {
-                throw new Exception("不支持");
-            }
-
-            return result;
-        }
-        #endregion
-
         #region InvokeValue
         public object InvokeValue(Expression exp)
         {