/// <summary>
/// Or连接条件
/// </summary>
/// <typeparam name="TEntity">实体类型</typeparam>
/// <param name="conditions">查询条件</param>
public void OrIfNotEmpty <TEntity>(params Expression <Func <TEntity, bool> >[] conditions)
{
if (conditions == null)
{
return;
}
foreach (var condition in conditions)
{
if (condition == null)
{
continue;
}
if (Lambdas.GetConditionCount(condition) > 1)
{
throw new InvalidOperationException(string.Format(LibraryResource.OnlyOnePredicate, condition));
}
if (string.IsNullOrWhiteSpace(Lambdas.GetValue(condition).SafeString()))
{
continue;
}
var predicate = _expressionResolver.Resolve(condition);
if (predicate == null)
{
continue;
}
Or(predicate);
}
}
/// <summary>
/// 设置查询条件
/// </summary>
/// <typeparam name="TEntity">实体类型</typeparam>
/// <param name="expression">查询条件表达式，如果参数值为空，则忽略该查询条件</param>
public void WhereIfNotEmpty <TEntity>(Expression <Func <TEntity, bool> > expression) where TEntity : class
{
if (expression == null)
{
throw new ArgumentNullException(nameof(expression));
}
if (Lambdas.GetConditionCount(expression) > 1)
{
throw new InvalidOperationException(string.Format(LibraryResource.OnlyOnePredicate, expression));
}
if (string.IsNullOrWhiteSpace(Lambdas.GetValue(expression).SafeString()))
{
return;
}
Where(expression);
}
/// <summary>
/// 获取查询条件表达式
/// </summary>
/// <typeparam name="TEntity">实体类型</typeparam>
/// <param name="predicate">查询条件,如果参数值为空，则忽略该查询条件，范例：t => t.Name == ""，该查询条件被忽略。
/// 注意：一次仅能添加一个条件，范例：t => t.Name == "a" && t.Mobile == "123"，不支持，将抛出异常</param>
public static Expression <Func <TEntity, bool> > GetWhereIfNotEmptyExpression <TEntity>(
Expression <Func <TEntity, bool> > predicate) where TEntity : class
{
if (predicate == null)
{
return(null);
}
if (Lambdas.GetConditionCount(predicate) > 1)
{
throw new InvalidOperationException(string.Format(LibraryResource.CanOnlyOneCondition, predicate));
}
var value = predicate.Value();
if (string.IsNullOrWhiteSpace(value.SafeString()))
{
return(null);
}
return(predicate);
}