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comparison Source/Data/Linq/Builder/ExpressionContext.cs @ 0:f990fcb411a9

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Копия текущей версии из github
author cin
date Thu, 27 Mar 2014 21:46:09 +0400
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-1:000000000000 0:f990fcb411a9
1 using System;
2 using System.Linq.Expressions;
3
4 namespace BLToolkit.Data.Linq.Builder
5 {
6 using BLToolkit.Linq;
7 using Data.Sql;
8
9 public class ExpressionContext : SequenceContextBase
10 {
11 public ExpressionContext(IBuildContext parent, IBuildContext sequence, LambdaExpression lambda)
12 : base(parent, sequence, lambda)
13 {
14 }
15
16 public ExpressionContext(IBuildContext parent, IBuildContext sequence, LambdaExpression lambda, SqlQuery sqlQuery)
17 : base(parent, sequence, lambda)
18 {
19 SqlQuery = sqlQuery;
20 }
21
22 public override Expression BuildExpression(Expression expression, int level)
23 {
24 throw new InvalidOperationException();
25 }
26
27 public override SqlInfo[] ConvertToSql(Expression expression, int level, ConvertFlags flags)
28 {
29 if (level == 0)
30 {
31 switch (flags)
32 {
33 case ConvertFlags.Field :
34 case ConvertFlags.Key :
35 case ConvertFlags.All :
36 {
37 var root = expression.GetRootObject();
38
39 if (root.NodeType == ExpressionType.Parameter)
40 {
41 var ctx = Builder.GetContext(this, root);
42
43 if (ctx != null)
44 {
45 if (ctx != this)
46 return ctx.ConvertToSql(expression, 0, flags);
47
48 return root == expression ?
49 Sequence.ConvertToSql(null, 0, flags) :
50 Sequence.ConvertToSql(expression, level + 1, flags);
51 }
52 }
53
54 break;
55 }
56 }
57
58 throw new InvalidOperationException();
59 }
60
61 throw new InvalidOperationException();
62 }
63
64 public override SqlInfo[] ConvertToIndex(Expression expression, int level, ConvertFlags flags)
65 {
66 throw new InvalidOperationException();
67 }
68
69 public override IsExpressionResult IsExpression(Expression expression, int level, RequestFor requestFlag)
70 {
71 switch (requestFlag)
72 {
73 case RequestFor.Root : return new IsExpressionResult(Lambda.Parameters.Count > 0 && expression == Lambda.Parameters[0]);
74
75 case RequestFor.Table :
76 case RequestFor.Association :
77 case RequestFor.Object :
78 case RequestFor.GroupJoin :
79 case RequestFor.Field :
80 case RequestFor.Expression :
81 {
82 var levelExpression = expression.GetLevelExpression(level);
83
84 return levelExpression == expression ?
85 Sequence.IsExpression(null, 0, requestFlag) :
86 Sequence.IsExpression(expression, level + 1, requestFlag);
87 }
88 }
89
90 return IsExpressionResult.False;
91 }
92
93 public override IBuildContext GetContext(Expression expression, int level, BuildInfo buildInfo)
94 {
95 if (expression == Lambda.Parameters[0])
96 return Sequence.GetContext(null, 0, buildInfo);
97
98 switch (expression.NodeType)
99 {
100 case ExpressionType.Constant :
101 case ExpressionType.New :
102 case ExpressionType.MemberInit : return null;
103 }
104
105 return Sequence.GetContext(expression, level + 1, buildInfo);
106 }
107 }
108 }