public System.Linq.Expressions.Expression GetConstructorExpression()
{
System.Linq.Expressions.ConstantExpression value = System.Linq.Expressions.Expression.Constant(this.Value, typeof(double));
System.Linq.Expressions.ConstantExpression units = System.Linq.Expressions.Expression.Constant(this.Units, typeof(PageUnits));
System.Linq.Expressions.NewExpression ctor = System.Linq.Expressions.Expression.New(ctorRef, value, units);
return(ctor);
}
public static void CreateMemberInitExpression()
{
System.Linq.Expressions.NewExpression newAnimal =
System.Linq.Expressions.Expression.New(typeof(Animal));
System.Reflection.MemberInfo speciesMember =
typeof(Animal).GetMember("Species")[0];
System.Reflection.MemberInfo ageMember =
typeof(Animal).GetMember("Age")[0];
// Create a MemberBinding object for each member
// that you want to initialize.
System.Linq.Expressions.MemberBinding speciesMemberBinding =
System.Linq.Expressions.Expression.Bind(
speciesMember,
System.Linq.Expressions.Expression.Constant("horse"));
System.Linq.Expressions.MemberBinding ageMemberBinding =
System.Linq.Expressions.Expression.Bind(
ageMember,
System.Linq.Expressions.Expression.Constant(12));
// Create a MemberInitExpression that represents initializing
// two members of the 'Animal' class.
System.Linq.Expressions.MemberInitExpression memberInitExpression =
System.Linq.Expressions.Expression.MemberInit(
newAnimal,
speciesMemberBinding,
ageMemberBinding);
Console.WriteLine(memberInitExpression.ToString());
// This code produces the following output:
//
// new Animal() {Species = "horse", Age = 12}
}
public ListInitExpression Update(System.Linq.Expressions.NewExpression newExpression, IEnumerable <ElementInit> initializers)
{
if ((newExpression == this.NewExpression) && (initializers == this.Initializers))
{
return(this);
}
return(Expression.ListInit(newExpression, initializers));
}
public MemberInitExpression Update(System.Linq.Expressions.NewExpression newExpression, IEnumerable <MemberBinding> bindings)
{
if ((newExpression == this.NewExpression) && (bindings == this.Bindings))
{
return(this);
}
return(Expression.MemberInit(newExpression, bindings));
}
static void New()
{
// <Snippet10>
// Create a NewExpression that represents constructing
// a new instance of Dictionary<int, string>.
System.Linq.Expressions.NewExpression newDictionaryExpression =
System.Linq.Expressions.Expression.New(typeof(Dictionary <int, string>));
Console.WriteLine(newDictionaryExpression.ToString());
// This code produces the following output:
//
// new Dictionary`2()
// </Snippet10>
}
static void ListInit()
{
// <Snippet7>
string tree1 = "maple";
string tree2 = "oak";
System.Reflection.MethodInfo addMethod = typeof(Dictionary <int, string>).GetMethod("Add");
// Create two ElementInit objects that represent the
// two key-value pairs to add to the Dictionary.
System.Linq.Expressions.ElementInit elementInit1 =
System.Linq.Expressions.Expression.ElementInit(
addMethod,
System.Linq.Expressions.Expression.Constant(tree1.Length),
System.Linq.Expressions.Expression.Constant(tree1));
System.Linq.Expressions.ElementInit elementInit2 =
System.Linq.Expressions.Expression.ElementInit(
addMethod,
System.Linq.Expressions.Expression.Constant(tree2.Length),
System.Linq.Expressions.Expression.Constant(tree2));
// Create a NewExpression that represents constructing
// a new instance of Dictionary<int, string>.
System.Linq.Expressions.NewExpression newDictionaryExpression =
System.Linq.Expressions.Expression.New(typeof(Dictionary <int, string>));
// Create a ListInitExpression that represents initializing
// a new Dictionary<> instance with two key-value pairs.
System.Linq.Expressions.ListInitExpression listInitExpression =
System.Linq.Expressions.Expression.ListInit(
newDictionaryExpression,
elementInit1,
elementInit2);
Console.WriteLine(listInitExpression.ToString());
// This code produces the following output:
//
// new Dictionary`2() {Void Add(Int32, System.String)(5,"maple"),
// Void Add(Int32, System.String)(3,"oak")}
// </Snippet7>
}
protected override System.Linq.Expressions.NewExpression VisitNew(System.Linq.Expressions.NewExpression nex)
{
int ndx = 0;
foreach (System.Linq.Expressions.Expression exp in nex.Arguments)
{
this._foundSpecialMethod = false;
this._foundAs = true;//New的方式都要加的
_strSql.Append(",");
_ParamSql.Append(",");
this.Visit(exp);
if (this.ExcuteType == DMSExcuteType.SELECT && this._CurrentMemberInfo != null)
{
MemberInfo memberInfo = nex.Members[ndx];
string text = GetMemberInfoName(memberInfo.Name);
if (text != this._CurrentMemberInfo.Name || this._foundSpecialMethod == true)
{
//增加As
this._strSql.Append(this.Provider.As);
if (this.SplitExpression.TableMapping.TokenFlag == true)
{
text = this.Provider.BuildColumnName(text);
}
this._strSql.Append(text);
this._ParamSql.Append(text);
}
else
{
if (this.SplitExpression.TableMapping.TokenFlag == true)
{
text = this.Provider.BuildColumnName(text);
}
this._ParamSql.Append(text);
}
}
ndx++;
}
return(nex);
}
internal ListInitExpression(System.Linq.Expressions.NewExpression newExpression, ReadOnlyCollection <ElementInit> initializers)
{
this._newExpression = newExpression;
this._initializers = initializers;
}
internal ListInitExpression(System.Linq.Expressions.NewExpression newExpression, ReadOnlyCollection<ElementInit> initializers)
{
this._newExpression = newExpression;
this._initializers = initializers;
}
internal MemberInitExpression(System.Linq.Expressions.NewExpression newExpression, ReadOnlyCollection <MemberBinding> bindings)
{
this._newExpression = newExpression;
this._bindings = bindings;
}
internal MemberInitExpression(System.Linq.Expressions.NewExpression newExpression, ReadOnlyCollection<MemberBinding> bindings)
{
this._newExpression = newExpression;
this._bindings = bindings;
}
protected override void PVisitNew(System.Linq.Expressions.NewExpression nex)
{
Push(walkerFactory.FromConstrucorNode(nex));
base.PVisitNew(nex);
}
