/// <summary> /// 获取 String 类型的 SQL 片断 /// </summary> /// <param name="value">值</param> /// <param name="dbType">数据类型</param> /// <param name="size">长度</param> /// <returns></returns> protected override string GetSqlValueOfString(object value, object dbType, int?size = null) { bool unicode = OracleUtils.IsUnicode(dbType); string result = this.EscapeQuote(value.ToString(), unicode, true); return(result); }
/// <summary> /// 访问 EndWidth 方法 /// </summary> /// <param name="m">方法表达式</param> protected override Expression VisitEndsWith(MethodCallExpression m) { _visitor.Visit(m.Object); if (this.NotOperands != null && this.NotOperands.Contains(m)) { _builder.Append(" NOT"); } _builder.Append(" LIKE "); if (m.Arguments[0].CanEvaluate()) { ColumnAttribute column = null; bool isUnicode = OracleUtils.IsUnicode(_visitedMark.Current, out column); string value = _constor.GetSqlValue(m.Arguments[0].Evaluate().Value, _builder.TranslateContext, column); if (!_builder.Parameterized && value != null) { value = value.TrimStart('N').Trim('\''); } if (_builder.Parameterized) { _builder.Append("('%' || "); _builder.Append(value); _builder.Append(")"); } else { if (isUnicode) { _builder.Append('N'); } _builder.Append("'%"); _builder.Append(value); _builder.Append("'"); } } else { _builder.Append("('%' || "); _visitor.Visit(m.Arguments[0]); _builder.Append(")"); } return(m); }
/// <summary> /// 检查字段或属性成员声明的 DbType 是否为 Unicode 数据类型 /// </summary> /// <param name="m">将要检查的字段或属性成员</param> /// <param name="column">字段或属性成员显示声明的列特性</param> /// <returns></returns> public static bool IsUnicode(MemberVisitedStack.VisitedMember m, out ColumnAttribute column) { column = m != null?TypeUtils.GetColumnAttribute(m.Member, m.ReflectedType) : null; return(OracleUtils.IsUnicode(column == null ? null : column.DbType)); }
/// <summary> /// 检查字段或属性成员声明的 DbType 是否为 Unicode 数据类型 /// </summary> /// <param name="m">将要检查的字段或属性成员</param> /// <returns></returns> public static bool IsUnicode(MemberVisitedStack.VisitedMember m) { ColumnAttribute column = null; return(OracleUtils.IsUnicode(m, out column)); }
/// <summary> /// 访问 ToString 方法 /// </summary> /// <param name="node">即将访问的表达式</param> protected override Expression VisitToStringImpl(Expression node) { // => a.ID.ToString() // 字符串不进行转换 if (node == null || node.Type == typeof(string)) { return(_visitor.Visit(node)); } ColumnAttribute column = null; bool isUnicode = OracleUtils.IsUnicode(_visitedMark.Current, out column); bool isBytes = node.Type == typeof(byte[]); bool isDate = node.Type == typeof(DateTime) || node.Type == typeof(DateTime?) || node.Type == typeof(TimeSpan) || node.Type == typeof(TimeSpan?) || node.Type == typeof(DateTimeOffset) || node.Type == typeof(DateTimeOffset?); if (!isBytes) { if (isUnicode) { _builder.Append("TO_NCHAR("); } else { _builder.Append("TO_CHAR("); } } // 其它类型转字符串 if (isDate) { _visitor.Visit(node); string format = string.Empty; ColumnAttribute c = _visitedMark.Current != null?TypeUtils.GetColumnAttribute(_visitedMark.Current.Member, _visitedMark.Current.ReflectedType) : null; if (c != null && OracleUtils.IsDate(c.DbType)) { format = "yyyy-mm-dd"; } else if (c != null && (OracleUtils.IsDateTime(c.DbType) || OracleUtils.IsDateTime2(c.DbType))) { format = "yyyy-mm-dd hh24:mi:ss.ff"; } else if (c != null && OracleUtils.IsDateTimeOffset(c.DbType)) { format = "yyyy-mm-dd hh24:mi:ss.ff tzh:tzm"; } // 没有显式指定数据类型,则根据表达式的类型来判断 if (string.IsNullOrEmpty(format)) { if (node.Type == typeof(DateTime) || node.Type == typeof(DateTime?)) { format = "yyyy-mm-dd hh24:mi:ss.ff"; } else if (node.Type == typeof(DateTimeOffset) || node.Type == typeof(DateTimeOffset?)) { format = "yyyy-mm-dd hh24:mi:ss.ff tzh:tzm"; } } if (!string.IsNullOrEmpty(format)) { _builder.Append(",'"); _builder.Append(format); _builder.Append("'"); } } else if (isBytes) { _builder.Append("RTRIM(DBMS_LOB.SUBSTR("); _visitor.Visit(node); _builder.Append(')'); } else if (node.Type == typeof(Guid)) { _builder.Append("REGEXP_REPLACE(REGEXP_REPLACE("); _visitor.Visit(node); _builder.Append(@",'(.{8})(.{4})(.{4})(.{4})(.{12})', '\1-\2-\3-\4-\5'),'(.{2})(.{2})(.{2})(.{2}).(.{2})(.{2}).(.{2})(.{2})(.{18})','\4\3\2\1-\6\5-\8\7\9')"); } else { _visitor.Visit(node); } _builder.Append(')'); return(node); }