private static Dictionary <string, List <Schema.Column> > MapFromNames(Schema schema, IEnumerable <KeyValuePair <ColumnRole, string> > roles, bool opt = false)
{
Contracts.AssertValue(schema);
Contracts.AssertValue(roles);
var map = new Dictionary <string, List <Schema.Column> >();
foreach (var kvp in roles)
{
Contracts.AssertNonEmpty(kvp.Key.Value);
if (string.IsNullOrEmpty(kvp.Value))
{
continue;
}
var info = schema.GetColumnOrNull(kvp.Value);
if (info.HasValue)
{
Add(map, kvp.Key.Value, info.Value);
}
else if (!opt)
{
throw Contracts.ExceptParam(nameof(schema), $"{kvp.Value} column '{kvp.Key.Value}' not found");
}
}
return(map);
}
/// <summary>
/// Get the value of the metadata, by metadata kind (aka column name).
/// </summary>
public void GetValue <TValue>(string kind, ref TValue value)
{
var column = Schema.GetColumnOrNull(kind);
if (column == null)
{
throw MetadataUtils.ExceptGetMetadata();
}
GetGetter <TValue>(column.Value.Index)(ref value);
}
/// <summary>
/// Get the value of the metadata, by metadata kind (aka column name).
/// </summary>
public void GetValue <TValue>(string kind, ref TValue value)
{
var column = Schema.GetColumnOrNull(kind);
if (column == null)
{
throw new InvalidOperationException("Invalid call to GetMetadata");
}
GetGetter <TValue>(column.Value.Index)(ref value);
}
/// <summary>
/// Legacy method to get the column index.
/// DO NOT USE: use <see cref="Schema.GetColumnOrNull"/> instead.
/// </summary>
public static bool TryGetColumnIndex(this Schema schema, string name, out int col)
{
col = schema.GetColumnOrNull(name)?.Index ?? -1;
return(col >= 0);
}
