/// <summary>
/// 判断字段模型是否是索引
/// </summary>
/// <param name="field"></param>
/// <returns>如果该字段模型是索引则返回索引信息,否则返回null</returns>
public static IDataModelFieldIndex IsIndexKey(this IDataFieldModel field)
{
return(DataModelHelper.GetExtendProperty_IndexKey(field.InnerExtend));
}
