如果你想列出/数组的整数，最简单的方法是接受逗号(，)分隔的字符串列表，并将其转换为整数列表。不要忘记提到[FromUri]属性。你的url看起来像:

... ?ID = 71&accountID = 1,2,3,289,56

public HttpResponseMessage test([FromUri]int ID, [FromUri]string accountID)
{
    List<int> accountIdList = new List<int>();
    string[] arrAccountId = accountId.Split(new char[] { ',' });
    for (var i = 0; i < arrAccountId.Length; i++)
    {
        try
        {
           accountIdList.Add(Int32.Parse(arrAccountId[i]));
        }
        catch (Exception)
        {
        }
    }
}

我的解决方案是创建一个属性来验证字符串，它做了一堆额外的公共功能，包括regex验证，你可以使用它来检查数字，然后我根据需要转换为整数…

你可以这样使用:

public class MustBeListAndContainAttribute : ValidationAttribute
{
    private Regex regex = null;
    public bool RemoveDuplicates { get; }
    public string Separator { get; }
    public int MinimumItems { get; }
    public int MaximumItems { get; }

    public MustBeListAndContainAttribute(string regexEachItem,
        int minimumItems = 1,
        int maximumItems = 0,
        string separator = ",",
        bool removeDuplicates = false) : base()
    {
        this.MinimumItems = minimumItems;
        this.MaximumItems = maximumItems;
        this.Separator = separator;
        this.RemoveDuplicates = removeDuplicates;

        if (!string.IsNullOrEmpty(regexEachItem))
            regex = new Regex(regexEachItem, RegexOptions.Compiled | RegexOptions.Singleline | RegexOptions.IgnoreCase);
    }

    protected override ValidationResult IsValid(object value, ValidationContext validationContext)
    {
        var listOfdValues = (value as List<string>)?[0];

        if (string.IsNullOrWhiteSpace(listOfdValues))
        {
            if (MinimumItems > 0)
                return new ValidationResult(this.ErrorMessage);
            else
                return null;
        };

        var list = new List<string>();

        list.AddRange(listOfdValues.Split(new[] { Separator }, System.StringSplitOptions.RemoveEmptyEntries));

        if (RemoveDuplicates) list = list.Distinct().ToList();

        var prop = validationContext.ObjectType.GetProperty(validationContext.MemberName);
        prop.SetValue(validationContext.ObjectInstance, list);
        value = list;

        if (regex != null)
            if (list.Any(c => string.IsNullOrWhiteSpace(c) || !regex.IsMatch(c)))
                return new ValidationResult(this.ErrorMessage);

        return null;
    }
}

你只需要在参数前添加[FromUri]，看起来像:

GetCategories([FromUri] int[] categoryIds)

并发送请求:

/Categories?categoryids=1&categoryids=2&categoryids=3 

如果有人需要-通过POST而不是FromUri来实现相同或类似的事情(如删除)，使用FromBody和客户端(JS/jQuery)格式参数为$。参数({":categoryids}， true)

c#:

public IHttpActionResult Remove([FromBody] int[] categoryIds)

jQuery:

$.ajax({
        type: 'POST',
        data: $.param({ '': categoryids }, true),
        url: url,
//...
});

关于$。Param ({": categoryids}， true)是。net期望post正文包含urlencoded的值，如=1&=2&=3，不带参数名，不带括号。

你可以尝试这段代码来获取逗号分隔的值/一个值数组来从webAPI返回JSON

 public class CategoryController : ApiController
 {
     public List<Category> Get(String categoryIDs)
     {
         List<Category> categoryRepo = new List<Category>();

         String[] idRepo = categoryIDs.Split(',');

         foreach (var id in idRepo)
         {
             categoryRepo.Add(new Category()
             {
                 CategoryID = id,
                 CategoryName = String.Format("Category_{0}", id)
             });
         }
         return categoryRepo;
     }
 }

 public class Category
 {
     public String CategoryID { get; set; }
     public String CategoryName { get; set; }
 } 

输出:

[
{"CategoryID":"4","CategoryName":"Category_4"}, 
{"CategoryID":"5","CategoryName":"Category_5"}, 
{"CategoryID":"3","CategoryName":"Category_3"} 
]

正如Filip W指出的那样，你可能不得不求助于这样的自定义模型绑定器(修改为绑定到实际的参数类型):

public IEnumerable<Category> GetCategories([ModelBinder(typeof(CommaDelimitedArrayModelBinder))]long[] categoryIds) 
{
    // do your thing
}

public class CommaDelimitedArrayModelBinder : IModelBinder
{
    public bool BindModel(HttpActionContext actionContext, ModelBindingContext bindingContext)
    {
        var key = bindingContext.ModelName;
        var val = bindingContext.ValueProvider.GetValue(key);
        if (val != null)
        {
            var s = val.AttemptedValue;
            if (s != null)
            {
                var elementType = bindingContext.ModelType.GetElementType();
                var converter = TypeDescriptor.GetConverter(elementType);
                var values = Array.ConvertAll(s.Split(new[] { ","},StringSplitOptions.RemoveEmptyEntries),
                    x => { return converter.ConvertFromString(x != null ? x.Trim() : x); });

                var typedValues = Array.CreateInstance(elementType, values.Length);

                values.CopyTo(typedValues, 0);

                bindingContext.Model = typedValues;
            }
            else
            {
                // change this line to null if you prefer nulls to empty arrays 
                bindingContext.Model = Array.CreateInstance(bindingContext.ModelType.GetElementType(), 0);
            }
            return true;
        }
        return false;
    }
}

然后你可以说:

/类别?categoryids=1,2,3,4和ASP。NET Web API将正确绑定您的categoryIds数组。