public static bool ToWhereClause(FilterSql context, List <FilterCriteria> findIn, Predicate <FilterCriteria> match)
{
if (context.Criteria != null)
{
context.Criteria.Clear(); // !
}
context.Criteria = findIn.FindAll(match);
return(ToWhereClause(context));
}
public static IQueryable ToFilter <TEntity>(this IQueryable query, List <FilterCriteria> criteria, string entityName)
{
var sql = new FilterSql();
if (ToWhereClause(sql, criteria, c => !c.IsInactive && c.Entity.IsCaseInsensitiveEqual(entityName)))
{
//query 保证存在 entity 实体关联，否则 entity.name 不成立
//WhereClause= " or entity.name =@{0}" EF 生成的SQL语句格式，非多表查询，可省略entity
//Values="123"
query = query.Where(sql.WhereClause.ToString(), sql.Values.ToArray());
}
return(query);
}
/// <summary>
///
/// </summary>
/// <param name="context"></param>
/// <returns></returns>
public static bool ToWhereClause(FilterSql context)
{
if (context.Values == null)
{
context.Values = new List <object>();
}
else
{
context.Values.Clear();
}
if (context.WhereClause == null)
{
context.WhereClause = new StringBuilder();
}
else
{
context.WhereClause.Clear();
}
int index = 0;
FilterParentheses(context.Criteria);
foreach (var itm in context.Criteria)
{
if (context.WhereClause.Length > 0)
{
context.WhereClause.AppendFormat(" {0} ", itm.Or ? "Or" : "And");
}
if (itm.Open.HasValue && itm.Open.Value)
{
context.WhereClause.Append("(");
}
if (!itm.Value.HasValue())
{
context.WhereClause.AppendFormat("ASCII({0}) Is Null", itm.SqlName); // true if null or empty (string)
}
else
{
context.WhereClause.Append(itm.SqlName);
if (itm.Operator == FilterOperator.Contains)
{
context.WhereClause.Append(".Contains(");
}
else if (itm.Operator == FilterOperator.StartsWith)
{
context.WhereClause.Append(".StartsWith(");
}
else if (itm.Operator == FilterOperator.EndsWith)
{
context.WhereClause.Append(".EndsWith(");
}
else
{
context.WhereClause.AppendFormat(" {0} ", itm.Operator == null ? "=" : itm.Operator.ToString());
}
context.WhereClause.Append(FormatParameterIndex(ref index));
if (itm.Operator == FilterOperator.Contains || itm.Operator == FilterOperator.StartsWith || itm.Operator == FilterOperator.EndsWith)
{
context.WhereClause.Append(")");
}
context.Values.Add(FilterValueToObject(itm.Value, itm.Type));
}
if (itm.Open.HasValue && !itm.Open.Value)
{
context.WhereClause.Append(")");
}
}
return(context.WhereClause.Length > 0);
}
