这个代码片段也很有用，它为您提供了一个包含错误消息的列表。

var errors = ModelState.Values。SelectMany(x => x. errors。Select(c => c. errormessage)).ToList();

我发现，按照到目前为止给出的答案中的建议，可以在不设置错误消息的情况下获得发生异常的情况，因此要捕获所有问题，确实需要同时获取ErrorMessage和Exception。

String messages = String.Join(Environment.NewLine, ModelState.Values.SelectMany(v => v.Errors)
                                                           .Select( v => v.ErrorMessage + " " + v.Exception));

或者作为一种扩展方法

public static IEnumerable<String> GetErrors(this ModelStateDictionary modelState)
{
      return modelState.Values.SelectMany(v => v.Errors)
                              .Select( v => v.ErrorMessage + " " + v.Exception).ToList();

}

这是对@Dunc的回答的扩展。参见xml文档注释

// ReSharper disable CheckNamespace
using System.Linq;
using System.Web.Mvc;


public static class Debugg
{
    /// <summary>
    /// This class is for debugging ModelState errors either in the quick watch 
    /// window or the immediate window.
    /// When the model state contains dozens and dozens of properties, 
    /// it is impossible to inspect why a model state is invalid.
    /// This method will pull up the errors
    /// </summary>
    /// <param name="modelState">modelState</param>
    /// <returns></returns>
    public static ModelError[]  It(ModelStateDictionary modelState)
    {
        var errors = modelState.Values.SelectMany(x => x.Errors).ToArray();
        return errors;            
    }
}

这个也有用:

var query = from state in ModelState.Values
    from error in state.Errors
    select error.ErrorMessage;
var errors = query.ToArray(); // ToList() and so on...

<div class=“textdanger”样式=“direction:rtl”asp-validation-summary=“All”></div>

简单地使用asp-validation-summary标签助手

var x = new Dictionary<string,string>();
for (var b = 0; b < ViewData.ModelState.Values.Count(); b++)
{
    if (ViewData.ModelState.Values.ElementAt(b).Errors.Count() > 0)
        x.Add(ViewData.ModelState.Keys.ElementAt(b), String.Join(",", ViewData
            .ModelState.Values.ElementAt(b).Errors.Select(c => c.ErrorMessage)));
}