将列表转换为逗号分隔的MySQL插入语句

Question

I've the following two classes;

public class CarModels
{
    public List<Model> Model{ get; set; }

    public CarModels()
    {
        Model = new List<Model>();
    }
}

public class Model
{
    public int ModelId { get; set; }
    public string Name { get; set; }
    public bool Enabled{ get; set; }
}

How can I extract the data into the format like

(ModelId,Name,Enabled),(ModelId,Name,Enabled),(ModelId,Name,Enabled) etc

Answer 1

String.Join(",", models.Select(m => String.Format("({0},{1},{2})", m.ModelId, m.Name, m.Enabled)));

That will give you string with False and True as Enabled values. If you want Enabled and Disabled instead, then use: m.Enabled ? "Enabled" : "Disabled" m.Enabled ? "Enabled" : "Disabled" when formatting model string.

---

Full sample (with NBuilder used to create sample models):

IEnumerable<Model> models = Builder<Model>.CreateListOfSize(3).Build();
Func<Model, string> formatModel = 
    m => String.Format("({0},{1},{2})", m.ModelId, m.Name, m.Enabled);
string result = String.Join(",", models.Select(formatModel));

Output:

(1,Name1,False),(2,Name2,True),(3,Name3,False)

Answer 2

Try this:

var models = carModels.Model.Aggregate<Model, string>("", (s, m) =>
{
    return s + String.Format(",({0},{1},{2})", m.ModelId, m.Name, m.Enabled);
}).Substring(1);