/// <summary>
/// 获取表达式所指的列特性
/// </summary>
/// <param name="sourceCommand">来源Sql语句</param>
/// <param name="expr">表达式</param>
/// <returns>表达式所指的列特性</returns>
internal static DatabaseColumnAttribute GetColumnAttribute(AbstractSqlCommand sourceCommand, MemberExpression expr)
{
DatabaseColumnAttribute attr = (sourceCommand != null && sourceCommand.SourceDatabaseTable != null ? sourceCommand.SourceDatabaseTable[expr.Member.Name] : null);
if (attr == null)
{
attr = EntityHelper.InternalGetColumnAttribute(expr.Member.DeclaringType, expr.Member.Name);
}
return attr;
}
/// <summary>
/// 获取一定包含数据类型的表达式所指的列特性
/// </summary>
/// <param name="sourceCommand">来源Sql语句</param>
/// <param name="expr">表达式</param>
/// <returns>表达式所指的列特性</returns>
internal static DatabaseColumnAttribute GetColumnAttributeWithDbType(AbstractSqlCommand sourceCommand, MemberExpression expr)
{
DatabaseColumnAttribute attr = ExpressionHelper.GetColumnAttribute(sourceCommand, expr);
if (attr != null && !attr.DbType.HasValue)
{
attr.DbType = DbTypeHelper.InternalGetDbType(expr.Type);
}
return attr;
}
/// <summary>
/// 初始化新的Sql语句抽象类
/// </summary>
/// <param name="database">数据库</param>
/// <param name="rootSource">创建时的根来源</param>
/// <param name="tableName">表格名称</param>
/// <exception cref="ArgumentNullException">数据库不能为空</exception>
protected AbstractSqlCommand(AbstractDatabase database, AbstractSqlCommand rootSource, String tableName)
{
if (database == null)
{
throw new ArgumentNullException("database");
}
this._database = database;
this._rootSource = rootSource;
this._tableName = tableName;
this._parameters = new List <DataParameter>();
this._parameterIndex = 0;
}
/// <summary>
/// 判断两个Sql语句是否相同
/// </summary>
/// <param name="obj">待比较的Sql语句</param>
/// <returns>两个Sql语句是否相同</returns>
public override Boolean Equals(Object obj)
{
if (obj == null)
{
return(false);
}
AbstractSqlCommand cmd = obj as AbstractSqlCommand;
if (cmd == null)
{
return(false);
}
if (this.CommandType != cmd.CommandType)
{
return(false);
}
if (!String.Equals(this.GetCommandText(), cmd.GetCommandText()))
{
return(false);
}
if (this._parameters.Count != cmd._parameters.Count)
{
return(false);
}
for (Int32 i = 0; i < this._parameters.Count; i++)
{
if ((this._parameters[i] != null && cmd._parameters[i] == null) || (this._parameters[i] == null && cmd._parameters[i] != null))
{
return(false);
}
if (!this._parameters[i].Equals(cmd._parameters[i]))
{
return(false);
}
}
return(true);
}
/// <summary>
/// 初始化新的有Where语句的Sql语句抽象类
/// </summary>
/// <param name="database">数据库</param>
/// <param name="rootSource">创建时的根来源</param>
/// <param name="tableName">表格名称</param>
protected AbstractSqlCommandWithWhere(AbstractDatabase database, AbstractSqlCommand rootSource, String tableName)
: base(database, rootSource, tableName)
{
this._conditionBuilder = new SqlConditionBuilder(this);
}
/// <summary>
/// 获取表达式所指的列名
/// </summary>
/// <param name="sourceCommand">来源Sql语句</param>
/// <param name="expr">表达式</param>
/// <returns>表达式所指的列名</returns>
internal static String GetColumnName(AbstractSqlCommand sourceCommand, MemberExpression expr)
{
DatabaseColumnAttribute attr = ExpressionHelper.GetColumnAttribute(sourceCommand, expr);
return (attr != null ? attr.ColumnName : String.Empty);
}
/// <summary>
/// 初始化Sql更新语句类
/// </summary>
/// <param name="database">数据库</param>
/// <param name="rootSource">创建时的根来源</param>
/// <param name="tableName">数据表名称</param>
internal UpdateCommand(AbstractDatabase database, AbstractSqlCommand rootSource, String tableName)
: base(database, rootSource, tableName)
{
this._updateFields = new List <DataParameter>();
}
/// <summary>
/// 初始化新的有Where语句的Sql语句抽象类
/// </summary>
/// <param name="database">数据库</param>
/// <param name="rootSource">创建时的根来源</param>
/// <param name="tableName">表格名称</param>
protected AbstractSqlCommandWithWhere(AbstractDatabase database, AbstractSqlCommand rootSource, String tableName)
: base(database, rootSource, tableName)
{
this._conditionBuilder = new SqlConditionBuilder(this);
}
/// <summary>
/// 初始化Sql删除语句类
/// </summary>
/// <param name="database">数据库</param>
/// <param name="rootSource">创建时的根来源</param>
/// <param name="tableName">数据表名称</param>
internal DeleteCommand(AbstractDatabase database, AbstractSqlCommand rootSource, String tableName)
: base(database, rootSource, tableName)
{
}
/// <summary>
/// 获取指定实体类的Sql语句参数集合
/// </summary>
/// <param name="cmd">Sql语句</param>
/// <param name="entity">实体类</param>
/// <returns>Sql语句参数集合</returns>
internal static SqlParameter[] InternalGetSqlParameters(AbstractSqlCommand cmd, Object entity)
{
List<SqlParameter> parameters = new List<SqlParameter>();
if (entity == null)
{
return parameters.ToArray();
}
Type entityType = entity.GetType();
PropertyInfo[] props = entityType.GetProperties();
foreach (PropertyInfo prop in props)
{
DatabaseColumnAttribute attr = null;
DbType? dbType = null;
Object[] objs = prop.GetCustomAttributes(TypeOfDatabaseColumnAttribute, true);
foreach (Object obj in objs)
{
if ((attr = obj as DatabaseColumnAttribute) != null)
{
break;
}
}
if (attr != null)
{
dbType = attr.DbType;
if (!dbType.HasValue)
{
dbType = DbTypeHelper.InternalGetDbType(prop.PropertyType);
}
SqlParameter parameter = cmd.CreateSqlParameter(attr.ColumnName, dbType.Value, prop.GetValue(entity, null));
parameters.Add(parameter);
}
}
return parameters.ToArray();
}
/// <summary>
/// 初始化新的Sql语句抽象类
/// </summary>
/// <param name="database">数据库</param>
/// <param name="rootSource">创建时的根来源</param>
/// <param name="tableName">表格名称</param>
/// <exception cref="ArgumentNullException">数据库不能为空</exception>
protected AbstractSqlCommand(AbstractDatabase database, AbstractSqlCommand rootSource, String tableName)
{
if (database == null)
{
throw new ArgumentNullException("database");
}
this._database = database;
this._rootSource = rootSource;
this._tableName = tableName;
this._parameters = new List<DataParameter>();
this._parameterIndex = 0;
}
