使用TreeListView将JSON数据显示到树结构中时出现InvalidCastException

时间:2014-05-28 18:05:39

标签: c# json .net objectlistview treelistview

我的JSON看起来像这样:

[
    {
        "id": 001,
        "name": "Item 1",
        "tree": [
            "010",
            "020",
            "030"
        ]
    },
    {
        "id": 002,
        "name": "Item 2",
        "tree": [
            "010",
            "020",
            "030"
        ]
    },
        {
        "id": 003,
        "name": "Item 3",
        "tree": [
            "010",
            "020",
            "030"
        ]
    }
]

可以将其建模为C#,如下所示:

public class Product
{
    public int id { get; set; }
    public string name { get; set; }
    public List<string> tree { get; set; }
}

我试图将此JSON数据显示到ObjectListView库中的TreeListView中。理想情况下,它看起来像这样。

enter image description here

我目前的代码如下,&#34;数据&#34;是TreeListView。

List<Product> Products = JsonConvert.DeserializeObject<List<Product>>(json);

data.CanExpandGetter = model => ((Product)model).tree.Count > 0;

data.ChildrenGetter = delegate(object model)
{
    return ((Product)model).
            tree;
};

data.SetObjects(Products);

但是,这会在System.InvalidCastException处抛出model => ((Product)model).tree.Count > 0

1 个答案:

答案 0 :(得分:0)

我找到了解决方案。我稍微改变了JSON布局。

public class ProductJSON
{
    public string id { get; set; }
    public string name { get; set; }
    public List<Tree> tree { get; set; }
}
public class Tree
{
    public string id { get; set; }
    public string name { get; set; }
}

public class Product
{
    public string id { get; set; }
    public string name { get; set; }
    public List<Product> tree { get; set; }
    public Product(string _id, string _name)
    {
        id = _id;
        name = _name;
        tree = new List<Product>();
    }   
}

...

List<ProductJSON> Products = JsonConvert.DeserializeObject<List<ProductJSON>>(json);

List<Product> ProductList = new List<Product>();
for(int i = 0; i < Products.Count; i++)
{
    ProductList.Add(new Product(Products[i].id, Products[i].name));
    foreach (Tree t in Products[i].tree)
    {
        ProductList[i].tree.Add(new Product(t.id, t.name));
    }
}
data.CanExpandGetter = delegate(object x) { return true; };
data.ChildrenGetter = delegate(object x) { return ((Product)x).tree; };
cID.AspectGetter = delegate(object x) { return String.Format("{0,3:D3}", ((Product)x).id); };
cName.AspectGetter = delegate(object x) { return ((Product)x).name; };
data.Roots = ProductList;