/// <summary>
/// 通过附加在指定类及其属性上的特性获取相关Schema缓存信息
/// </summary>
public static SchemaCache CreateByAttribute(Type type)
{
SchemaCache cache = new SchemaCache();
cache.Type = type;
cache.PropertyAccessor = new PropertyAccessor();
//获取类符合要求的属性
cache.PropertyInfos = cache.Type.GetProperties()?.Where(PropertyFilter)?.ToArray();
cache.TableSchema = GetTableSchema(cache.Type);
if (cache.PropertyInfos != null)
{
cache.PropertyAccessor.Initlialize(cache.PropertyInfos.Length);
foreach (PropertyInfo propertyInfo in cache.PropertyInfos)
{
ColumnSchema schema = GetColumnSchema(propertyInfo);
cache.PropertyAccessor.BuildingGetPropertyCache(propertyInfo);
cache.PropertyAccessor.BuildingSetPropertyCache(propertyInfo);
cache.ColumnSchemas.Add(propertyInfo.Name, schema);
cache.ColumnNames.Add(schema.Name);
}
}
return(cache);
}
///【置于调用链末尾】 对当前的查询做分页操作。sorter 分页字段，此处返回 model 的指定属性。start 起始位置。 count 获取数量。asc 默认升序，置为 false 改为降序
/// </summary>
public static IDriver <T> Page <T>(this IDriver <T> driver, Expression <Func <T, Object> > sorter, Int32 start, Int32 count, Boolean asc = true)
where T : class
{
String sortColName = null;
SchemaCache schema = Table <T> .Schema;
MemberExpression expression = null;
if (sorter.Body.NodeType != ExpressionType.MemberAccess)
{
//由于函数签名为 Object 类型 所以值类型 属性会发生装箱
if (sorter.Body.NodeType == ExpressionType.Convert)
{
UnaryExpression unaryExp = sorter.Body as UnaryExpression;
expression = unaryExp.Operand as MemberExpression;
}
else
{
throw new ArgumentException(nameof(sorter));
}
}
else
{
expression = sorter.Body as MemberExpression;
}
sortColName = schema.GetColumnName(expression.Member.Name);
return(Page <T>(driver, sortColName, start, count, asc));
}
internal static void AnalyingIn <T>(DbProvider dbProvider, Expression <Func <T, Object> > filter, SQLComponent component, Object[] values)
where T : class
{
MemberExpression expression;
ExpressionType noteType = filter.Body.NodeType;;
switch (noteType)
{
case ExpressionType.Convert:
UnaryExpression unary = filter.Body as UnaryExpression;
expression = (MemberExpression)unary.Operand;
break;
case ExpressionType.MemberAccess:
{
expression = filter.Body as MemberExpression;
}
break;
default:
throw new ArgumentException(nameof(filter));;
}
SchemaCache schema = Table <T> .Schema;
var colSchema = schema.GetColumnSchema(expression.Member.Name);
String columnName = colSchema.Name;
columnName = String.Format(dbProvider.ConflictFreeFormat, columnName);
columnName = String.Format(CommonFormat.COLUMN_FORMAT, schema.TableName, columnName);
StringBuilder inParaNames = new StringBuilder();
Int32 count = values.Length;
String paraSymbol = "inPara";
for (Int32 i = 0; i < count; ++i)
{
String paraName = dbProvider.Prefix + paraSymbol + ParaCounter <T> .CountString;
inParaNames.Append(paraName);
if (i != (count - 1))
{
inParaNames.Append(SqlKeyWord.COMMA);
}
DbParameter parameter = dbProvider.DbParameter(
paraName, values[i], colSchema.DbType
);
component.AddParameter(parameter);
}
component.AppendSQL(columnName);
component.AppendSQL(SqlKeyWord.IN);
component.AppendSQLFormat(CommonFormat.BRACKET_FORMAT, inParaNames.ToString());
}
/// <summary>
/// 增大指定数值字段的值
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="tableObj"></param>
/// <param name="field"></param>
/// <param name="number"></param>
/// <returns></returns>
public static IDriver <T> Increment <T>(this Table <T> tableObj, Expression <Func <T, Object> > field, Double number = 1) where T : class
{
IDriver <T> driver = tableObj.DbProvider.Driver <T>();
var expression = (field.Body as UnaryExpression);
var mexp = expression.Operand as MemberExpression;
if (mexp == null)
{
throw new ArgumentException(nameof(field));
}
SchemaCache schema = Table <T> .Schema;
var colSchema = schema.GetColumnSchema(mexp.Member.Name);
String columnName = OrmAssistor.BuildColumnName(colSchema, tableObj.DbProvider.ConflictFreeFormat, schema.TableName);
String setSql = columnName + SqlKeyWord.EQUAL + columnName + SqlKeyWord.PLUS + number.ToString();
String sql = String.Format(BasicSqlFormat.UPDATE_FORMAT, schema.TableName, setSql);
driver.SQLComponent.AppendSQL(sql);
return(driver);
}
