本文整理汇总了C#中CodeWriter.GetNullExpression方法的典型用法代码示例。如果您正苦于以下问题：C# CodeWriter.GetNullExpression方法的具体用法？C# CodeWriter.GetNullExpression怎么用？C# CodeWriter.GetNullExpression使用的例子？那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类CodeWriter的用法示例。
在下文中一共展示了CodeWriter.GetNullExpression方法的5个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的C#代码示例。
示例1: WriteClassHeader
public override void WriteClassHeader(CodeWriter writer, DbLinq.Schema.Dbml.Table table, GenerationContext context)
{
using (writer.WriteRegion(string.Format("{0} handling", typeof(INotifyPropertyChanging).Name)))
{
const string eventName = "PropertyChanging"; // do not change, part of INotifyPropertyChanging
const string emptyArgs = "emptyChangingEventArgs";
// event
writer.WriteEvent(SpecificationDefinition.Public, eventName, typeof(PropertyChangingEventHandler).Name);
writer.WriteLine();
// empty event arg
writer.WriteField(SpecificationDefinition.Private | SpecificationDefinition.Static,
writer.GetAssignmentExpression(emptyArgs, writer.GetNewExpression(
writer.GetMethodCallExpression(typeof(PropertyChangingEventArgs).Name, "\"\""))),
typeof(PropertyChangingEventArgs).Name);
// method
using (writer.WriteMethod(SpecificationDefinition.Protected | SpecificationDefinition.Virtual,
sendPropertyChangingMethod, null))
{
using (writer.WriteIf(writer.GetDifferentExpression(eventName, writer.GetNullExpression())))
{
writer.WriteLine(writer.GetStatement(writer.GetMethodCallExpression(eventName,
writer.GetThisExpression(), emptyArgs)));
}
}
}
}示例2: WriteClassHeader
public override void WriteClassHeader(CodeWriter writer, DbLinq.Schema.Dbml.Table table, GenerationContext context)
{
using (writer.WriteRegion(string.Format("{0} handling", typeof(INotifyPropertyChanged).Name)))
{
const string eventName = "PropertyChanged"; // do not change, part of INotifyPropertyChanged
const string propertyNameName = "propertyName";
// event
writer.WriteEvent(SpecificationDefinition.Public, eventName, typeof(PropertyChangedEventHandler).Name);
writer.WriteLine();
// method
using (writer.WriteMethod(SpecificationDefinition.Protected | SpecificationDefinition.Virtual,
sendPropertyChangedMethod, null, new ParameterDefinition { Name = propertyNameName, Type = typeof(string) }))
{
using (writer.WriteIf(writer.GetDifferentExpression(eventName, writer.GetNullExpression())))
{
writer.WriteLine(writer.GetStatement(writer.GetMethodCallExpression(eventName,
writer.GetThisExpression(),
writer.GetNewExpression(writer.GetMethodCallExpression(typeof(PropertyChangedEventArgs).Name,
propertyNameName)))));
}
}
}
}示例3: WriteClassEqualsAndHash
protected virtual void WriteClassEqualsAndHash(CodeWriter writer, Table table, GenerationContext context)
{
List<DbLinq.Schema.Dbml.Column> primaryKeys = table.Type.Columns.Where(c => c.IsPrimaryKey).ToList();
if (primaryKeys.Count == 0)
{
writer.WriteLine("#warning L189 table {0} has no primary key. Multiple C# objects will refer to the same row.",
table.Name);
return;
}
using (writer.WriteRegion(string.Format("GetHashCode(), Equals() - uses column {0} to look up objects in liveObjectMap",
string.Join(", ", primaryKeys.Select(pk => pk.Member).ToList().ToArray()))))
{
// GetHashCode
using (writer.WriteMethod(SpecificationDefinition.Public | SpecificationDefinition.Override,
"GetHashCode", typeof(int)))
{
string hashCode = null;
foreach (var primaryKey in primaryKeys)
{
var member = writer.GetVariableExpression(primaryKey.Storage);
string primaryKeyHashCode = writer.GetMethodCallExpression(writer.GetMemberExpression(member, "GetHashCode"));
if (primaryKey.CanBeNull
|| GetType(primaryKey.Type, false).IsClass) // this patch to ensure that even if DB does not allow nulls,
// our in-memory object won't generate a fault
{
var isNullExpression = writer.GetEqualExpression(member, writer.GetNullExpression());
var nullExpression = writer.GetLiteralValue(0);
primaryKeyHashCode = "(" + writer.GetTernaryExpression(isNullExpression, nullExpression, primaryKeyHashCode) + ")";
}
if (string.IsNullOrEmpty(hashCode))
hashCode = primaryKeyHashCode;
else
hashCode = writer.GetXOrExpression(hashCode, primaryKeyHashCode);
}
writer.WriteLine(writer.GetReturnStatement(hashCode));
}
writer.WriteLine();
// Equals
string otherAsObject = "o";
using (writer.WriteMethod(SpecificationDefinition.Public | SpecificationDefinition.Override,
"Equals", typeof(bool), new ParameterDefinition { Type = typeof(object), Name = otherAsObject }))
{
string other = "other";
writer.WriteLine(writer.GetStatement(writer.GetAssignmentExpression(
writer.GetDeclarationExpression(other, table.Type.Name),
writer.GetCastExpression(otherAsObject, table.Type.Name,
false))));
using (writer.WriteIf(writer.GetEqualExpression(other, writer.GetNullExpression())))
{
writer.WriteLine(writer.GetReturnStatement(writer.GetLiteralValue(false)));
}
string andExpression = null;
foreach (var primaryKey in primaryKeys)
{
var member = writer.GetVariableExpression(primaryKey.Storage);
string primaryKeyTest = writer.GetMethodCallExpression(
writer.GetMemberExpression(
writer.GetMemberExpression(
writer.GetGenericName("System.Collections.Generic.EqualityComparer", primaryKey.Type),
"Default"),
"Equals"),
member,
writer.GetMemberExpression(other, member));
if (string.IsNullOrEmpty(andExpression))
andExpression = primaryKeyTest;
else
andExpression = writer.GetAndExpression(andExpression, primaryKeyTest);
}
writer.WriteLine(writer.GetReturnStatement(andExpression));
}
}
}示例4: WriteClassChildrenAttachment
/// <summary>
/// Writes attach/detach method
/// </summary>
/// <param name="writer"></param>
/// <param name="table"></param>
/// <param name="schema"></param>
/// <param name="context"></param>
protected virtual void WriteClassChildrenAttachment(CodeWriter writer, Table table, Database schema, GenerationContext context)
{
var children = GetClassChildren(table).ToList();
if (children.Count > 0)
{
using (writer.WriteRegion("Attachement handlers"))
{
foreach (var child in children)
{
// the reverse child is the association seen from the child
// we're going to use it...
var reverseChild = schema.GetReverseAssociation(child);
// ... to get the parent name
var memberName = reverseChild.Member;
var entityParameter = new ParameterDefinition { Name = "entity", LiteralType = child.Type };
// the Attach event handler sets the child entity parent to "this"
using (writer.WriteMethod(SpecificationDefinition.Private, GetChildAttachMethodName(child),
null, entityParameter))
{
writer.WriteLine(
writer.GetStatement(
writer.GetAssignmentExpression(
writer.GetMemberExpression(entityParameter.Name, memberName),
writer.GetThisExpression())));
}
writer.WriteLine();
// the Detach event handler sets the child entity parent to null
using (writer.WriteMethod(SpecificationDefinition.Private, GetChildDetachMethodName(child),
null, entityParameter))
{
writer.WriteLine(
writer.GetStatement(
writer.GetAssignmentExpression(
writer.GetMemberExpression(entityParameter.Name, memberName),
writer.GetNullExpression())));
}
writer.WriteLine();
}
}
}
}示例5: WriteClassParent
protected virtual void WriteClassParent(CodeWriter writer, Association parent, bool hasDuplicates, Database schema, GenerationContext context)
{
// the following is apparently useless
DbLinq.Schema.Dbml.Table targetTable = schema.Tables.FirstOrDefault(t => t.Type.Name == parent.Type);
if (targetTable == null)
{
//Logger.Write(Level.Error, "ERROR L191 target table type not found: " + parent.Type + " (processing " + parent.Name + ")");
return;
}
string member = parent.Member;
string storageField = parent.Storage;
// TODO: remove this
if (member == parent.ThisKey)
{
member = parent.ThisKey + targetTable.Type.Name; //repeat name to prevent collision (same as Linq)
storageField = "_x_" + parent.Member;
}
writer.WriteField(SpecificationDefinition.Private, storageField,
writer.GetGenericName(TypeExtensions.GetShortName(typeof(EntityRef<>)),
targetTable.Type.Name));
var storageAttribute = NewAttributeDefinition<AssociationAttribute>();
storageAttribute["Storage"] = storageField;
storageAttribute["OtherKey"] = parent.OtherKey;
storageAttribute["ThisKey"] = parent.ThisKey;
storageAttribute["Name"] = parent.Name;
storageAttribute["IsForeignKey"] = parent.IsForeignKey;
SpecificationDefinition specifications;
if (parent.AccessModifierSpecified)
specifications = GetSpecificationDefinition(parent.AccessModifier);
else
specifications = SpecificationDefinition.Public;
if (parent.ModifierSpecified)
specifications |= GetSpecificationDefinition(parent.Modifier);
var propertyName = hasDuplicates
? member + "_" + string.Join("", parent.TheseKeys.ToArray())
: member;
using (writer.WriteAttribute(storageAttribute))
using (writer.WriteAttribute(NewAttributeDefinition<DebuggerNonUserCodeAttribute>()))
using (writer.WriteProperty(specifications, propertyName, targetTable.Type.Name))
{
string storage = writer.GetMemberExpression(storageField, "Entity");
using (writer.WritePropertyGet())
{
writer.WriteLine(writer.GetReturnStatement(storage));
}
using (writer.WritePropertySet())
{
// algorithm is:
// 1.1. must be different than previous value
// 1.2. or HasLoadedOrAssignedValue is false (but why?)
// 2. implementations before change
// 3. if previous value not null
// 3.1. place parent in temp variable
// 3.2. set [Storage].Entity to null
// 3.3. remove it from parent list
// 4. assign value to [Storage].Entity
// 5. if value is not null
// 5.1. add it to parent list
// 5.2. set FK members with entity keys
// 6. else
// 6.1. set FK members to defaults (null or 0)
// 7. implementationas after change
//writer.WriteLine(writer.GetStatement(writer.GetAssignmentExpression(storage, writer.GetPropertySetValueExpression())));
var entityMember = writer.GetMemberExpression(parent.Storage, "Entity");
// 1.1
using (writer.WriteIf(writer.GetDifferentExpression(writer.GetPropertySetValueExpression(),
entityMember)))
{
var otherAssociation = schema.GetReverseAssociation(parent);
// 2. code before the change
// TODO change interface to require a member instead of a column
//foreach (IImplementation implementation in context.Implementations())
// implementation.WritePropertyBeforeSet(writer, ???, context);
// 3.
using (writer.WriteIf(writer.GetDifferentExpression(entityMember, writer.GetNullExpression())))
{
var previousEntityRefName = "previous" + parent.Type;
// 3.1.
writer.WriteLine(writer.GetStatement(
writer.GetVariableDeclarationInitialization(parent.Type, previousEntityRefName, entityMember)
));
// 3.2.
writer.WriteLine(writer.GetStatement(
writer.GetAssignmentExpression(entityMember, writer.GetNullExpression())
));
// 3.3.
writer.WriteLine(writer.GetStatement(
writer.GetMethodCallExpression(
writer.GetMemberExpression(writer.GetMemberExpression(previousEntityRefName, otherAssociation.Member), "Remove"),
writer.GetThisExpression())
));
}
// 4.
//.........这里部分代码省略.........