private CPQuery GeUpdateQuery()
{
if (_setProxy == null)
{
throw new InvalidOperationException("请先调用Set方法。");
}
if (_whereProxy == null)
{
throw new InvalidOperationException("请先调用Where方法。");
}
CPQuery update = _setProxy.GetUpdateQuery(null);
CPQuery where = _whereProxy.GetWhereQuery();
CPQuery query = update + where;
return(query);
}
/// <summary>
/// 根据指定的实体属性，生成UPDATE的语句，并执行数据库插入操作
/// </summary>
/// <returns></returns>
public int Update()
{
if (_setProxy == null)
{
throw new InvalidOperationException("请先调用Set方法。");
}
if (_whereProxy == null)
{
throw new InvalidOperationException("请先调用Where方法。");
}
CPQuery update = _setProxy.GetUpdateQuery(null);
CPQuery where = _whereProxy.GetWhereQuery();
CPQuery query = update + where;
return(query.ExecuteNonQuery());
}
/// <summary>
/// 根据已修改的实体属性，生成INSERT语句，并执行数据库插入操作，
/// 注意：此方法只能在实体的代理对象上调用。
/// </summary>
/// <returns>数据库操作过程中影响的行数</returns>
public int Insert()
{
IEntityProxy proxy = this as IEntityProxy;
if (proxy == null)
{
throw new InvalidOperationException("请在调用BeginEdit()的返回值对象上调用Insert方法。");
}
CPQuery insert = GetInsertQuery();
if (insert == null)
{
return(-1);
}
proxy.ClearChangeFlags(); // 清除修改标记，防止多次调用
return(insert.ExecuteNonQuery());
}
/// <summary>
/// 根据已修改的实体属性，生成DELETE查询条件，并执行数据库插入操作，
/// 注意：此方法只能在实体的代理对象上调用。
/// </summary>
/// <returns>数据库操作过程中影响的行数</returns>
public int Delete()
{
IEntityProxy proxy = this as IEntityProxy;
if (proxy == null)
{
throw new InvalidOperationException("请在调用BeginEdit()的返回值对象上调用Delete方法。");
}
CPQuery where = GetWhereQuery();
if (where == null)
{
return(-1); // 不允许没有WHERE条件的删除，如果确实需要，请手工写SQL
}
CPQuery query = this.DbContext.CreateCPQuery()
+ "DELETE FROM " + GetTableName() + where;
proxy.ClearChangeFlags(); // 清除修改标记，防止多次调用
return(query.ExecuteNonQuery());
}
private CPQuery GetInsertQueryCommand()
{
IEntityProxy proxy = this as IEntityProxy;
if (proxy == null)
{
throw new InvalidOperationException("请在调用BeginEdit()的返回值对象上调用Insert方法。");
}
CPQuery insert = GetInsertQuery();
if (insert == null)
{
return(null);
}
proxy.ClearChangeFlags(); // 清除修改标记，防止多次调用
return(insert);
}
internal CPQuery GetInsertQuery()
{
IEntityProxy proxy = this as IEntityProxy;
string[] names = proxy.GetChangeNames();
object[] values = proxy.GetChangeValues();
if (names.Length == 0)
{
return(null); // 没有设置任何属性，应该不会发生吧？
}
CPQuery query = this.DbContext.CreateCPQuery();
query = query
+ "INSERT INTO " + GetTableName() + "("
+ string.Join(",", names.ToArray())
+ ") VALUES (";
for (int i = 0; i < values.Length; i++)
{
object value = values[i];
if (value == null)
{
query = query + "NULL";
}
else
{
query = query + new QueryParameter(value);
}
if (i < values.Length - 1)
{
query.AppendSql(",");
}
}
query.AppendSql(")");
return(query);
}
private void SetInArrayParameter(string placeholder, ICollection collection)
{
StringBuilder sb = new StringBuilder(128);
// 优先检查 int[], Guid[] 类型，并转成SQL语句中的一部分
// 因为这些强类型的数据本身是安全的，不存在注入，就不转换成命令参数。
CPQuery.ArrayToString(collection, sb);
if (sb.Length == 0) // 如果不是 int[], Guid[] ，就转换成命令参数
{
foreach (object obj in collection)
{
string name = "x" + (_paramIndex++).ToString();
DbParameter parameter = _command.CreateParameter();
parameter.ParameterName = ParaNameBuilder.GetParaName(name);
parameter.Value = obj;
_command.Parameters.Add(parameter);
if (sb.Length > 0)
{
sb.Append(',');
}
sb.Append(ParaNameBuilder.GetPlaceholder(name));
}
}
if (sb.Length == 0)
{
sb.Append("NULL");
}
_command.CommandText = _command.CommandText.Replace(placeholder, sb.ToString());
}
/// <summary>
/// 根据指定的实体属性，生成UPDATE的语句，并执行数据库插入操作
/// </summary>
/// <returns></returns>
public int Update()
{
CPQuery query = GeUpdateQuery();
return(query.ExecuteNonQuery());
}
/// <summary>
/// 将指定的字符串（T-SQL的片段）转成CPQuery对象
/// </summary>
/// <param name="sql">T-SQL的片段的字符串</param>
/// <returns>包含T-SQL的片段的CPQuery对象</returns>
public static CPQuery AsCPQuery(this string sql)
{
return(CPQuery.Create(sql));
}
/// <summary>
/// 根据Where调用产生的查询条件获取实体对象列表
/// </summary>
/// <returns></returns>
public async Task <List <T> > ToListAsync()
{
CPQuery query = GetSelectQuery();
return(await query.ToListAsync <T>());
}
/// <summary>
/// 根据Where调用产生的查询条件获取实体对象列表
/// </summary>
/// <returns></returns>
public List <T> ToList()
{
CPQuery query = GetSelectQuery();
return(query.ToList <T>());
}
/// <summary>
/// 根据Where调用产生的查询条件获取单个实体对象
/// </summary>
/// <returns></returns>
public async Task <T> ToSingleAsync()
{
CPQuery query = GetSelectQuery();
return(await query.ToSingleAsync <T>());
}
/// <summary>
/// 根据Where调用产生的查询条件获取单个实体对象
/// </summary>
/// <returns></returns>
public T ToSingle()
{
CPQuery query = GetSelectQuery();
return(query.ToSingle <T>());
}
/// <summary>
/// 根据指定的实体属性，生成UPDATE的语句，并执行数据库插入操作
/// </summary>
/// <returns></returns>
public async Task <int> UpdateAsync()
{
CPQuery query = GeUpdateQuery();
return(await query.ExecuteNonQueryAsync());
}
/// <summary>
/// 根据指定的实体属性，生成INSERT语句，并执行数据库插入操作
/// </summary>
/// <returns></returns>
public int Insert()
{
CPQuery query = GetInsertQuery();
return(query.ExecuteNonQuery());
}
/// <summary>
/// 根据指定的实体属性，生成DELETE查询条件，并执行数据库插入操作
/// </summary>
/// <returns></returns>
public int Delete()
{
CPQuery query = GetDeleteQuery();
return(query.ExecuteNonQuery());
}
/// <summary>
/// 根据指定的实体属性，生成INSERT语句，并执行数据库插入操作
/// </summary>
/// <returns></returns>
public async Task <int> InsertAsync()
{
CPQuery query = GetInsertQuery();
return(await query.ExecuteNonQueryAsync());
}
