/// <summary>
/// 利用反射将ExcelDataRow转换为制定类型，性能较差
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="row"></param>
/// <returns></returns>
private static T ConvertByRefelection <T>(this ExcelDataRow row, IEnumerable <PropertyInfo> props = null)
{
if (props == null)
{
props = typeof(T).GetProperties();
}
object o = Activator.CreateInstance(typeof(T));
props.ToList().ForEach(p =>
{
ExcelDataCol col = null;
if (p.IsDefined(typeof(ColNameAttribute)))
{
col = row.DataCols.SingleOrDefault(c => c.ColName == p.GetCustomAttribute <ColNameAttribute>().ColName);
}
else
{
col = row.DataCols.SingleOrDefault(c => c.ColName == p.Name);
}
if (col != null)
{
p.SetValue(o, ExpressionMapper.ChangeType(col.ColValue, p.PropertyType));
}
});
return((T)o);
}
private static object GetValue(ExcelDataRow row, Type propType, string colName)
{
string val = row.DataCols.SingleOrDefault(c => c.ColName == colName)?.ColValue;
if (!string.IsNullOrWhiteSpace(val))
{
return(ExpressionMapper.ChangeType(val, propType));
}
return(val);
}
private static Func <List <ExcelDataCol>, T> GetFunc <T>(ExcelDataRow row)
{
string propertyNames = string.Empty;
row.DataCols.ForEach(c => propertyNames += c.PropertyName + "_");
var key = typeof(T).FullName + "_" + propertyNames.Trim('_');
var props = typeof(T).GetProperties().Where(x => x.CanWrite && x.CanRead);
Func <List <ExcelDataCol>, T> func = ExpressionMapper.GetFunc <T>(key, props);
return(func);
}
/// <summary>
/// 利用表达式树，将ExcelDataRow集合快速转换为指定类型集合
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="rows"></param>
/// <returns></returns>
private static IEnumerable <T> ConvertByExpressionTree <T>(this IEnumerable <ExcelDataRow> rows)
{
if (rows == null || rows.Count() <= 0)
{
return(null);
}
Func <List <ExcelDataCol>, T> func = GetFunc <T>(rows.ToList()[0]);
List <T> list = new List <T>();
rows?.ToList().ForEach(r =>
{
var item = ExpressionMapper.FastConvert(r, func);
list.Add(item);
}
);
return(list);
}