/// <summary>
/// 创建指定数据列提交单元成员。
/// </summary>
/// <param name="column">指定数据列。</param>
/// <param name="generator">值生成对象。</param>
/// <param name="customExpression">自定义表达式。</param>
/// <returns>创建结果。</returns>
protected CommitMember CreateCommitUnitMember(ColumnMetadata column, ValueGenerateBase generator, DbExpression customExpression = null)
{
var context = this.GenerateContext;
if (generator == null)
{
if (customExpression != null)
{
return(ReisterReturnMember(new CommitExpressionMember(column, generator, customExpression)));
}
else
{
return(new CommitMember(column));
}
}
else
{
switch (generator.GeneratedOption)
{
case EGeneratedOption.Expression:
var expression = generator as ValueGenerateExpression;
return(ReisterReturnMember(new CommitExpressionMember(column, generator, context.Translate(expression.Expression))));
case EGeneratedOption.Database:
case EGeneratedOption.Identity:
return(ReisterReturnMember(new CommitMember(column, generator, ECommitValueType.Database)));
case EGeneratedOption.Ignore:
case EGeneratedOption.Memory:
if (customExpression != null)
{
return(ReisterReturnMember(new CommitExpressionMember(column, generator, customExpression)));
}
else
{
return(new CommitMember(column));
}
default:
throw new NotSupportedException(string.Format(Res.NotSupportedGeneratedOption, generator.GeneratedOption));
}
}
}
/// <summary>
/// 创建提交成员。
/// </summary>
/// <param name="metadata">列元数据。</param>
/// <param name="generator">值生成对象。</param>
/// <param name="expression">当前值的表达式。</param>
public CommitExpressionMember(ColumnMetadata metadata, ValueGenerateBase generator, DbExpression expression)
: base(metadata, generator, ECommitValueType.Expression)
{
Expression = expression;
}
private ValueGenerateBase CreateGenerate(GeneratedValueBaseAttribute attr, EGeneratedPurpose purpose, ValueGenerateBase source)
{
if (source == null && (attr.GeneratedPurpose & purpose) == purpose)
{
switch (attr.GeneratedOption)
{
case EGeneratedOption.Ignore: return(IgnoreValueGenerate);
case EGeneratedOption.Identity: return(new ValueGenerateIdentity());
case EGeneratedOption.Database: return(new ValueGenerateDatabase());
case EGeneratedOption.Memory:
var memoryAttr = (GeneratedMemoryValueAttribute)attr;
return(new ValueGenerateMemory(memoryAttr.GeneratorType));
case EGeneratedOption.Expression:
var expAttr = (GeneratedExpressionAttribute)attr;
return(new ValueGenerateExpression(expAttr.Expression));
}
}
return(source);
}
/// <summary>
/// 创建普通提交成员。
/// </summary>
/// <param name="metadata">列元数据。</param>
/// <param name="gnerator">值生成器。</param>
/// <param name="columnType">列提交类型。</param>
public CommitMember(ColumnMetadata metadata, ValueGenerateBase gnerator, ECommitValueType columnType)
{
Metadata = metadata;
Generator = gnerator;
ValueType = columnType;
}
