-

OrmTest/ExpressionTest/Select.cs

@@ -13,10 +13,11 @@ namespace OrmTest.ExpressionTest
     {
         internal static void Init()
         {
-            Expression<Func<Student, object>> exp = it => new Program() { x = it.Name };
+            Expression<Func<Student, object>> exp = it => new Program() { x = "a" };
             ExpressionContext expContext = new ExpressionContext(exp, ResolveExpressType.WhereSingle);
             expContext.ResolveType = ResolveExpressType.SelectSingle;
-            var x = expContext.Result;
+            expContext.Resolve();
+            var x = expContext.Result.GetString();
         }
     }
 }

SqlSugar/ExpressionsToSql/Common/ExpressionResult.cs

@@ -40,7 +40,7 @@ namespace SqlSugar
         public string GetString()
         {
             if (_Result == null) return null;
-            return _Result.ToString();
+            return _Result.ToString().TrimEnd(',');
         }
         #region functions
         public string[] GetResultArray()
@@ -64,6 +64,7 @@ namespace SqlSugar
                 case ResolveExpressType.WhereMultiple:
                     break;
                 case ResolveExpressType.SelectSingle:
+                    parameter=parameter + ",";
                     break;
                 case ResolveExpressType.SelectMultiple:
                     break;

SqlSugar/ExpressionsToSql/Common/ExpressionTool.cs

@@ -47,7 +47,7 @@ namespace SqlSugar
             }
         }
 
-        public static object GetValue(MemberInfo member, Expression expression)
+        public static object GetMemberValue(MemberInfo member, Expression expression)
         {
             var memberInfos = new Stack<MemberInfo>();
             var fieldInfo = member as System.Reflection.FieldInfo;
@@ -168,5 +168,14 @@ namespace SqlSugar
 
             return value;
         }
+
+        public static Type GetPropertyOrFieldType(MemberInfo propertyOrField)
+        {
+            if (propertyOrField.MemberType == MemberTypes.Property)
+                return ((PropertyInfo)propertyOrField).PropertyType;
+            if (propertyOrField.MemberType == MemberTypes.Field)
+                return ((FieldInfo)propertyOrField).FieldType;
+            throw new NotSupportedException();
+        }
     }
 }

SqlSugar/ExpressionsToSql/ExpressionContext.cs

@@ -45,6 +45,8 @@ namespace SqlSugar
         {
             get
             {
+                if (base._Parameters == null)
+                    base._Parameters = new List<SugarParameter>();
                 return base._Parameters;
             }
             set
@@ -66,6 +68,11 @@ namespace SqlSugar
         {
             return name;
         }
+        public virtual void Resolve()
+        {
+            BaseResolve resolve = new BaseResolve(new ExpressionParameter() { Expression = this.Expression, Context = this });
+            resolve.Start();
+        }
         #endregion
     }
 }

SqlSugar/ExpressionsToSql/ResolveItems/MemberConstExpressionResolve.cs

@@ -13,7 +13,7 @@ namespace SqlSugar
         {
             var expression = base.Expression as MemberExpression;
             var isLeft = parameter.IsLeft;
-            object value = ExpressionTool.GetValue(expression.Member, expression);
+            object value = ExpressionTool.GetMemberValue(expression.Member, expression);
             if (parameter.BaseParameter.BinaryExpressionInfoList != null)
             {
                 parameter.BaseParameter.BinaryExpressionInfoList.Add(new KeyValuePair<string, BinaryExpressionInfo>(ExpressionConst.BinaryExpressionInfoListKey, new BinaryExpressionInfo()

SqlSugar/ExpressionsToSql/ResolveItems/MemberInitExpressionResolve.cs

@@ -2,6 +2,7 @@
 using System.Collections.Generic;
 using System.Linq;
 using System.Linq.Expressions;
+using System.Reflection;
 using System.Text;
 using System.Threading.Tasks;
 namespace SqlSugar
@@ -18,6 +19,7 @@ namespace SqlSugar
                 case ResolveExpressType.WhereMultiple:
                     break;
                 case ResolveExpressType.SelectSingle:
+                    SelectSingle(expression, parameter);
                     break;
                 case ResolveExpressType.SelectMultiple:
                     break;
@@ -29,5 +31,45 @@ namespace SqlSugar
                     break;
             }
         }
+
+        private void SelectSingle(MemberInitExpression expression, ExpressionParameter parameter)
+        {
+            int i = 0;
+            foreach (MemberBinding binding in expression.Bindings)
+            {
+                ++i;
+                if (binding.BindingType != MemberBindingType.Assignment)
+                {
+                    throw new NotSupportedException();
+                }
+                MemberAssignment memberAssignment = (MemberAssignment)binding;
+                MemberInfo member = memberAssignment.Member;
+                Type memberType = ExpressionTool.GetPropertyOrFieldType(member);
+                var name = memberType.Name;
+                var isValueType = memberType.IsValueType || memberType == ExpressionConst.StringType;
+                if (isValueType)
+                {
+                    if (memberAssignment.Expression.NodeType==ExpressionType.Constant)
+                    {
+                        var value= ((ConstantExpression)memberAssignment.Expression).Value;
+                        string parameterName = this.Context.SqlParameterKeyWord + "constant" + i;
+                        parameter.Context.Result.Append(parameterName);
+                        this.Context.Parameters.Add(new SugarParameter(parameterName, value));
+                    }
+                    else
+                    {
+                        var memberExpression = (MemberExpression)memberAssignment.Expression;
+                        var fieldNme = (memberExpression).Member.Name;
+                        parameter.Context.Result.Append(fieldNme);
+                    }
+                }
+                else
+                {
+
+
+                }
+            }
+        }
+
     }
 }