/// <summary>
/// Creates a row by fetching it from a result set.
/// </summary>
/// <param name="result">The result.</param>
/// <returns></returns>
internal static MySqlRow FetchFromResult(MySqlResult result)
{
// fetch data
IntPtr valueArr = MySqlNative.mysql_fetch_row(result.Handle);
if (valueArr == IntPtr.Zero)
{
return(null);
}
IntPtr lengthArr = MySqlNative.mysql_fetch_lengths(result.Handle);
int numFields = (int)MySqlNative.mysql_num_fields(result.Handle);
// create row
MySqlRow row = new MySqlRow();
row.result = result;
row.values = new object[numFields];
// lengths
long[] length = new long[numFields];
Marshal.Copy(lengthArr, length, 0, numFields);
// values
IntPtr[] valuePtrs = new IntPtr[numFields];
Marshal.Copy(valueArr, valuePtrs, 0, numFields);
for (int i = 0; i < numFields; i++)
{
row.values[i] = result.Fields[i].CastFrom(Marshal.PtrToStringAnsi(valuePtrs[i]));
}
return(row);
}
/// <summary>
/// Fetches the next row and casts it to a model.
/// </summary>
/// <typeparam name="T"></typeparam>
/// <returns></returns>
/// <exception cref="System.Exception">
/// The provided type must be a model
/// or
/// The provided model has no attribute
/// or
/// The provided model does not match the table
/// or
/// The model field ' + field.Name + ' has no attribute
/// </exception>
public T Fetch <T>()
{
// test
if (!typeof(Model).IsAssignableFrom(typeof(T)))
{
throw new Exception("The provided type must be a model");
}
// get type data
Type t = typeof(T);
// get model attributes
ModelAttribute modelAtt = t.GetCustomAttribute <ModelAttribute>();
// check table
if (modelAtt.Name.ToLower() != Fields[0].Table.ToLower())
{
throw new Exception("The provided model does not match the table");
}
// create
object obj = null;
// fetch
MySqlRow row = Fetch();
if (row == null)
{
return(default(T));
}
// get fields
foreach (FieldInfo field in t.GetFields())
{
// get field attributes
ModelFieldAttribute fieldAtt = field.GetCustomAttribute <ModelFieldAttribute>();
// find mysql field
for (int i = 0; i < Fields.Length; i++)
{
if (Fields[i].Name == fieldAtt.Name)
{
if (fieldAtt.Primary)
{
obj = Activator.CreateInstance(typeof(T), row.Values[i]);
}
else if (obj == null)
{
throw new Exception("The model does not define a valid primary key");
}
field.SetValue(obj, row.Values[i]);
}
}
}
return((T)obj);
}
/// <summary>
/// Fetches the next row in the set.
/// </summary>
/// <returns></returns>
public MySqlRow Fetch()
{
if (fields == null)
{
FetchFields();
}
return(MySqlRow.FetchFromResult(this));
}
