本文整理汇总了C#中Connection.IsDBNull方法的典型用法代码示例。如果您正苦于以下问题：C# Connection.IsDBNull方法的具体用法？C# Connection.IsDBNull怎么用？C# Connection.IsDBNull使用的例子？那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类Connection的用法示例。
在下文中一共展示了Connection.IsDBNull方法的3个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的C#代码示例。
示例1: GetValue
internal object GetValue(int i,Connection conn){
if (IsDBNull(i,conn))
return null;
if (_tableFieldCounts.ContainsKey(i))
{
Table t = (Table)LazyProxy.Instance(_tableFields[_fieldNames[i]].GetConstructor(System.Type.EmptyTypes).Invoke(new object[0]));
sTableField[] flds = conn.Pool.Mapping[_tableFields[_fieldNames[i]]].Fields;
int index = 0;
i = TranslateFieldIndex(i);
foreach (sTableField fld in flds)
{
PropertyInfo pi = t.GetType().GetProperty(fld.ClassProperty, Utility._BINDING_FLAGS_WITH_INHERITANCE);
if (!pi.PropertyType.IsArray || !pi.PropertyType.Equals(typeof(byte[])))
{
if (conn.Pool.Mapping.IsMappableType(pi.PropertyType) && !Utility.IsEnum(pi.PropertyType))
{
if (!conn.IsDBNull(i + index))
{
if (t.GetField(pi.Name) == null)
{
Table tmp = (Table)LazyProxy.Instance(pi.PropertyType.GetConstructor(Type.EmptyTypes).Invoke(new object[0]));
tmp.LoadStatus = LoadStatus.Partial;
t.SetField(fld.Name, tmp);
}
Table tbl = (Table)t.GetField(pi.Name);
foreach (sTableField f in conn.Pool.Mapping[tbl.GetType()].Fields)
{
if (fld.ExternalField == f.Name)
{
t.RecurSetPropertyValue(f.Name, conn, conn.GetName(i + index), tbl);
index++;
break;
}
}
}
else
index++;
}
else
{
if (!conn.IsDBNull(i + index))
{
if (Utility.IsEnum(pi.PropertyType))
t.SetField(fld.ClassProperty, conn.Pool.GetEnumValue(pi.PropertyType, conn.GetInt32(i + index)));
else
t.SetField(fld.ClassProperty, conn[i + index]);
}
index++;
}
}
}
t.LoadStatus = LoadStatus.Complete;
return t;
}
else if (_enumFields.ContainsKey(i))
{
return _pool.GetEnumValue(_enumFields[i], conn.GetInt32(TranslateFieldIndex(i)));
}else
return conn.GetValue(TranslateFieldIndex(i));
}示例2: IsDBNull
internal bool IsDBNull(int i,Connection conn)
{
if (!_tableFieldCounts.ContainsKey(i))
return conn.IsDBNull(TranslateFieldIndex(i));
else
{
int start = TranslateFieldIndex(i);
for (int x = 0; x < _tableFieldCounts[i]; x++)
{
if (!conn.IsDBNull(x + start))
return false;
}
return true;
}
}示例3: Init
public void Init(Connection conn)
{
_tables = new List<ExtractedTableMap>();
_triggers = new List<Trigger>();
_generators = new List<Generator>();
_identities = new List<IdentityField>();
_views = new List<View>();
_procedures = new List<StoredProcedure>();
_createdTypes = new List<Type>();
conn.ExecuteQuery(conn.Pool.queryBuilder.SelectTriggers());
while (conn.Read())
{
//patch to handle long trigger code from mssql
if (_triggers.Count > 0)
{
if (_triggers[_triggers.Count - 1].Name == (string)conn[0])
_triggers[_triggers.Count - 1] = new Trigger((string)conn[0], (string)conn[1], _triggers[_triggers.Count - 1].Code + (string)conn[2]);
else
_triggers.Add(new Trigger((string)conn[0], (string)conn[1], (string)conn[2]));
}else
_triggers.Add(new Trigger((string)conn[0], (string)conn[1], (string)conn[2]));
}
conn.Close();
conn.ExecuteQuery(conn.Pool.queryBuilder.SelectProcedures());
while (conn.Read())
{
_procedures.Add(new StoredProcedure(conn[0].ToString(), conn[1].ToString(), conn[2].ToString(), conn[3].ToString(), conn[4].ToString()));
}
conn.Close();
conn.ExecuteQuery(conn.queryBuilder.SelectViews());
while (conn.Read())
_views.Add(new View((string)conn[0], (string)conn[1]));
conn.Close();
conn.ExecuteQuery(conn.queryBuilder.SelectTableNames());
while (conn.Read())
{
_tables.Add(new ExtractedTableMap((string)conn[0]));
}
conn.Close();
for (int x = 0; x < _tables.Count; x++)
{
ExtractedTableMap etm = _tables[x];
etm.Indices = conn.queryBuilder.ExtractTableIndexes(etm.TableName, conn);
conn.ExecuteQuery(conn.queryBuilder.SelectTableFields(etm.TableName));
while (conn.Read())
{
etm.Fields.Add(new ExtractedFieldMap(conn[0].ToString(), conn[1].ToString(),
long.Parse(conn[2].ToString()), bool.Parse(conn[3].ToString()), bool.Parse(conn[4].ToString()),
bool.Parse(conn[5].ToString()),
(conn.IsDBNull(6) ? null : conn[6].ToString())));
}
conn.Close();
conn.ExecuteQuery(conn.queryBuilder.SelectForeignKeys(etm.TableName));
while (conn.Read())
{
etm.ForeignFields.Add(new ForeignRelationMap(conn[5].ToString(), conn[0].ToString(), conn[1].ToString(),
conn[2].ToString(), conn[3].ToString(), conn[4].ToString()));
}
conn.Close();
_tables.RemoveAt(x);
_tables.Insert(x, etm);
}
if (conn.UsesGenerators)
{
conn.ExecuteQuery(conn.queryBuilder.SelectGenerators());
while (conn.Read())
{
_generators.Add(new Generator((string)conn[0]));
}
conn.Close();
for (int x = 0; x < _generators.Count; x++)
{
Generator gen = _generators[x];
conn.ExecuteQuery(conn.queryBuilder.GetGeneratorValue(gen.Name));
conn.Read();
gen.Value = long.Parse(conn[0].ToString());
conn.Close();
_generators.RemoveAt(x);
_generators.Insert(x, gen);
}
}
if (conn.UsesIdentities)
{
conn.ExecuteQuery(conn.queryBuilder.SelectIdentities());
while (conn.Read())
{
_identities.Add(new IdentityField((string)conn[0], (string)conn[1], (string)conn[2], (string)conn[3]));
}
conn.Close();
}
}