public override string ResolveSum(LambdaExpression selector)
{
if (selector == null)
{
throw new ArgumentException("selector");
}
var selectSql = "";
switch (selector.NodeType)
{
case ExpressionType.Lambda:
case ExpressionType.MemberAccess:
{
EntityObject entityObject = EntityCache.QueryEntity(selector.Parameters[0].Type);
var memberName = selector.Body.GetCorrectPropertyName();
selectSql = $@" SELECT NVL(SUM({entityObject.GetAsName(providerOption)}
{providerOption.CombineFieldName(entityObject.FieldPairs[memberName])}),0) ";
}
break;
case ExpressionType.MemberInit:
throw new DapperExtensionException("不支持该表达式类型");
}
return(selectSql);
}
