/// <summary>
/// Converts a constant from one quotation data type to another.
/// </summary>
/// <param name="originalValue">Original value to convert.</param>
/// <param name="oldDataType">Old data type.</param>
/// <param name="newDataType">New data type.</param>
/// <returns>Converted constant.</returns>
protected virtual object ConvertConstantQuotation(object originalValue, QuotationDataType oldDataType, QuotationDataType newDataType)
{
var oldExpression = originalValue as LambdaExpressionSlim ?? oldDataType.GetExpression(originalValue).ToExpressionSlim();
var newExpression = Parent.Apply(oldExpression);
return(newDataType.CreateInstance(newExpression));
}
protected override bool EqualsQuotation(object expected, object actual, QuotationDataType expectedDataType, QuotationDataType actualDataType)
{
return(EqualsExpressionCore(expected, actual));
}
/// <summary>
/// Checks if a constant can be converted from one quotation data type to another.
/// </summary>
/// <param name="newValue">Converted value.</param>
/// <param name="oldDataType">Old data type.</param>
protected virtual void CheckConstantQuotation(Object newValue, QuotationDataType oldDataType)
{
}
protected override bool EqualsQuotation(object expected, object actual, QuotationDataType expectedDataType, QuotationDataType actualDataType)
{
return(ExpressionComparator.Equals((Expression)expected, (Expression)actual));
}
/// <summary>
/// QuotationDataType的格式化方法
/// </summary>
/// <param name="qdt"></param>
/// <returns></returns>
public static string ToFormatString(this QuotationDataType qdt)
{
return(((int)qdt).ToString("00"));
}
protected override Type MakeQuotation(QuotationDataType type, Type functionType)
{
return(typeof(Expression <>).MakeGenericType(functionType));
}
protected override LambdaExpression MakeQuotation(QuotationDataType type, LambdaExpression functionType)
{
Debug.Assert(functionType == null);
return(MakeExpressionCore(type.UnderlyingType));
}
protected override LambdaExpression VisitQuotation(QuotationDataType type)
{
// No need to recurse into function type, this will be serialized as an expression anyway.
return(MakeQuotation(type, functionType: null));
}