static async Task <int> UpdateOnly <TEntity>(IDbContext dbContext, TEntity entity, string[] fields, bool @async)
{
PublicHelper.CheckNull(dbContext);
PublicHelper.CheckNull(entity);
PublicHelper.CheckNull(fields);
/* 支持 context.UpdateOnly<User>(user, "Name,Age", "NickName"); */
fields = fields.SelectMany(a => a.Split(',')).Select(a => a.Trim()).ToArray();
if (fields.Length == 0)
{
throw new ArgumentException("fields");
}
Type entityType = typeof(TEntity);
TypeDescriptor typeDescriptor = EntityTypeContainer.GetDescriptor(entityType);
List <MemberBinding> bindings = new List <MemberBinding>();
ConstantExpression entityConstantExp = Expression.Constant(entity);
foreach (string field in fields)
{
MemberInfo memberInfo = entityType.GetMember(field)[0];
var propertyDescriptor = typeDescriptor.FindPrimitivePropertyDescriptor(memberInfo);
if (propertyDescriptor == null)
{
throw new ArgumentException(string.Format("Could not find the member '{0}' from entity.", propertyDescriptor.Column.Name));
}
Expression entityMemberAccess = Expression.MakeMemberAccess(entityConstantExp, memberInfo);
MemberAssignment bind = Expression.Bind(memberInfo, entityMemberAccess);
bindings.Add(bind);
}
ParameterExpression parameter = Expression.Parameter(entityType, "a");
Expression conditionBody = null;
foreach (PrimitivePropertyDescriptor primaryKey in typeDescriptor.PrimaryKeys)
{
Expression propOrField = Expression.PropertyOrField(parameter, primaryKey.Property.Name);
Expression keyValue = Expression.MakeMemberAccess(entityConstantExp, primaryKey.Property);
Expression e = Expression.Equal(propOrField, keyValue);
conditionBody = conditionBody == null ? e : Expression.AndAlso(conditionBody, e);
}
Expression <Func <TEntity, bool> > condition = Expression.Lambda <Func <TEntity, bool> >(conditionBody, parameter);
return(await UpdateOnly(dbContext, condition, bindings, @async));
}
static MemberInfo TryGetMapMember(List <MemberInfo> members, string readerName, TypeDescriptor typeDescriptor)
{
MemberInfo mapMember = null;
foreach (MemberInfo member in members)
{
string columnName = null;
if (typeDescriptor != null)
{
PrimitivePropertyDescriptor propertyDescriptor = typeDescriptor.FindPrimitivePropertyDescriptor(member);
if (propertyDescriptor != null)
{
columnName = propertyDescriptor.Column.Name;
}
}
if (string.IsNullOrEmpty(columnName))
{
ColumnAttribute columnAttribute = member.GetCustomAttribute <ColumnAttribute>();
if (columnAttribute != null)
{
columnName = columnAttribute.Name;
}
}
if (string.IsNullOrEmpty(columnName))
{
continue;
}
if (!string.Equals(columnName, readerName, StringComparison.OrdinalIgnoreCase))
{
continue;
}
mapMember = member;
break;
}
if (mapMember == null)
{
mapMember = members.Find(a => a.Name == readerName);
}
if (mapMember == null)
{
mapMember = members.Find(a => string.Equals(a.Name, readerName, StringComparison.OrdinalIgnoreCase));
}
return(mapMember);
}
