泛型摘录

一段类型转化

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 ///

            /// Gets the value.            ///             ///             /// Name of the column.             ///             public T GetValue (string columnName)             {                 columnName = columnName.ToLowerInvariant();                 object oVal;

                try                {                    oVal = this[columnName].CurrentValue;                }                catch                {                    throw new ArgumentException("There's no column called '" + columnName + "' for this object", "columnName");                }

                if(oVal == null || oVal == DBNull.Value)                    return default(T);

                Type type = typeof(T);

                if(type == typeof(object))                    return (T)oVal;

                // handle nullable type conversion                if(IsNullable(type))                {                    NullableConverter converter = new NullableConverter(type);                    type = converter.UnderlyingType;                }

                //if (IsNullable(type) || type == typeof(object))                //{                //    if (type == typeof(bool?))                //        return (T)(object)Convert.ToBoolean(oVal);                //    return (T)oVal;                //}

                //if (type == typeof(Guid))                //    return (T)(object)new Guid(oVal.ToString());

                Type valType = oVal.GetType();                if(valType == typeof(Byte[]))                    return (T)Convert.ChangeType(oVal, valType);

                return (T)Convert.ChangeType(oVal, type);            }