/// <summary>
/// memberAccessor==value
/// </summary>
/// <param name="memberAccessor"></param>
/// <param name="value"></param>
/// <returns></returns>
protected virtual Expression GetEqualExpression(MemberExpression memberAccessor, object value)
{
Expression constant = ConstantExpression(ChangeValueTypeToMemberType(memberAccessor.Type, value));
MemberExpression nullableStructValueAccessor = memberAccessor.GetNullableStructValueAccessExpression();
if (nullableStructValueAccessor == null || (nullableStructValueAccessor != null && value == null))
{
return(Expression.Equal(memberAccessor, constant));
}
else
{
return(Expression.Equal(nullableStructValueAccessor, constant).AttachAndAlsoMemberNotNullCheckExpressionOnLeft(memberAccessor));
}
}
protected virtual Expression GetGreaterThanOrEqualExpression(MemberExpression memberAccessor, object value)
{
if (value is null)
{
throw new ArgumentNullException(nameof(value));
}
//member>=constant
Expression constant = ConstantExpression(ChangeValueTypeToMemberType(memberAccessor.Type, value));
MemberExpression nullableStructValueAccessor = memberAccessor.GetNullableStructValueAccessExpression();
if (nullableStructValueAccessor == null)
{
return(Expression.GreaterThanOrEqual(memberAccessor, constant));
}
else
{
return(Expression.GreaterThanOrEqual(nullableStructValueAccessor, constant).AttachAndAlsoMemberNotNullCheckExpressionOnLeft(memberAccessor));
}
}
protected virtual Expression GetInExpression(MemberExpression memberAccessor, object value)
{
if (value is null)
{
throw new ArgumentNullException(nameof(value));
}
Expression result = null;
MemberExpression nullableStructValueAccessor = memberAccessor.GetNullableStructValueAccessExpression();
MemberExpression currentMemberAccessor = nullableStructValueAccessor == null ? memberAccessor : nullableStructValueAccessor;
foreach (object item in (IEnumerable)value)
{
Expression constant = ConstantExpression(ChangeValueTypeToMemberType(memberAccessor.Type, item));
result = result == null
? Expression.Equal(currentMemberAccessor, constant)
: Expression.OrElse(result, Expression.Equal(currentMemberAccessor, constant));
}
if (nullableStructValueAccessor != null)
{
result = result.AttachAndAlsoMemberNotNullCheckExpressionOnLeft(memberAccessor);
}
return(result);
}
protected virtual Expression GetBetweenExpression(MemberExpression memberAccessor, object value)
{
//member>=constant[0]&&member<=constant[1]
if (value is object[] valueArray)
{
MemberExpression nullableStructValueAccessor = memberAccessor.GetNullableStructValueAccessExpression();
MemberExpression currentMemberAccessor = nullableStructValueAccessor != null ? nullableStructValueAccessor : memberAccessor;
Expression constantStart = ConstantExpression(ChangeValueTypeToMemberType(currentMemberAccessor.Type, valueArray[0]));
Expression constantEnd = ConstantExpression(ChangeValueTypeToMemberType(currentMemberAccessor.Type, valueArray[1]));
Expression result = Expression.AndAlso(
Expression.GreaterThanOrEqual(currentMemberAccessor, constantStart),
Expression.LessThanOrEqual(currentMemberAccessor, constantEnd)
);
if (nullableStructValueAccessor != null)
{
result = result.AttachAndAlsoMemberNotNullCheckExpressionOnLeft(memberAccessor);
}
return(result);
}
else
{
throw new ArgumentException(nameof(value) + " must be array which length==2", nameof(value));
}
}