CODEWITHSUNDEEP
asp.net-mvcmodelstate
chobo2
chobo2

Reputation: 85715

How to get all Errors from ASP.Net MVC modelState?

I want to get all the error messages out of the modelState without knowing the key values. Looping through to grab all the error messages that the ModelState contains.

How can I do this?

Upvotes: 544

Views: 434535

Answers (22)

Moumit
Moumit

Reputation: 9510

With fieldName ..

 if (!this.ModelState.IsValid)
 {
     foreach (var modelState in this.ModelState)
     { 
         foreach (var error in modelState.Value.Errors)
         {
             rModel.AddError(error.ErrorMessage, ErrorType.Error, modelState.Key);
         }
     }

     rModel.Message = "Invalid Data";
     return false;
 }

Upvotes: 0

Jivan Bhandari
Jivan Bhandari

Reputation: 860

Anybody looking for asp.net core 3.1. The answer includes key (field name). Most of other answers include only errors.

I found that this is what [ApiController] returns

 Dictionary<string, List<string>> errors = new Dictionary<string, List<string>>();

                foreach (KeyValuePair<string, ModelStateEntry> kvp in ViewData.ModelState)
                {
                    string key = kvp.Key;
                    ModelStateEntry entry = kvp.Value;

                    if (entry.Errors.Count > 0)
                    {
                        List<string> errorList = new List<string>();
                        foreach (ModelError error in entry.Errors)
                        {
                            errorList.Add(error.ErrorMessage);
                        }

                        errors[key] = errorList;
                    }
                }

                return  new JsonResult(new {Errors = errors});

Upvotes: 7

hossein.sharifipour
hossein.sharifipour

Reputation: 111

get error with Field Name and Error Message

var errors = new List<ErrorDto>();
foreach (KeyValuePair<string, ModelStateEntry> kvp in context.ModelState)
{
    if (kvp.Value.Errors.Count > 0)
    {
        errors.Add(new ErrorDto()
        {
            FieldName = kvp.Key,
            ErrorMessage = string.Join(",", kvp.Value.Errors.Select(v => v.ErrorMessage))
        });
    }
}

Error Model

    public class ErrorDto
    {
        public string FieldName { get; set; }
        public string ErrorMessage { get; set; }
    }

Upvotes: 1

r_piramoon
r_piramoon

Reputation: 211

This code snippet is useful too and give you a List that contains of Error Messges.

var errors = ModelState.Values.SelectMany(x => x.Errors.Select(c => c.ErrorMessage)).ToList();

Upvotes: 10

dpricop
dpricop

Reputation: 121

For AJAX Request better solution:

    public IActionResult Demo(DemoInfo formData)
    {
        if (!ModelState.IsValid)
        {
            IEnumerable<object> formErrors = ModelState.Select((s) => new { 
                fieldName = s.Key, 
                fieldValue = s.Value.RawValue,
                fieldMessage = s.Value.Errors.FirstOrDefault()?.ErrorMessage
            });
            return Json(new { formValid = 0, formErrors });
        }
        return Json(new { formValid = 1 });
    }

Response format will be:

{"formValid":0,
 "formErrors":[{
     "fieldName":"name of field from object",
     "fieldValue":"value from browser",
     "fieldMessage":null /*Error message from model annotations if field is valid the value will be null */
 }]
}

For more details about Func<> check this page : Func<TSource,Int32,TResult>)

Upvotes: 5

mostafa kazemi
mostafa kazemi

Reputation: 565

var result = string.Join(',',ModelState.Values.SelectMany(v => v.Errors).Select(a=>a.ErrorMessage));

Upvotes: -1

vagnerbezerraf
vagnerbezerraf

Reputation: 21

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)));
}

Upvotes: 0

Armin Azhdari
Armin Azhdari

Reputation: 71

<div class="text-danger" style="direction:rtl" asp-validation-summary="All"></div>

simply use asp-validation-summary Tag Helper

Upvotes: 5

Josh Sutterfield
Josh Sutterfield

Reputation: 1988

Outputting just the Error messages themselves wasn't sufficient for me, but this did the trick. 

var modelQuery = (from kvp in ModelState
                  let field = kvp.Key
                  let state = kvp.Value
                  where state.Errors.Count > 0
                  let val = state.Value?.AttemptedValue ?? "[NULL]"

                  let errors = string.Join(";", state.Errors.Select(err => err.ErrorMessage))
                  select string.Format("{0}:[{1}] (ERRORS: {2})", field, val, errors));

Trace.WriteLine(string.Join(Environment.NewLine, modelQuery));

Upvotes: 7

Yasser Shaikh
Yasser Shaikh

Reputation: 47774

I was able to do this using a little LINQ, 

public static List<string> GetErrorListFromModelState
                                              (ModelStateDictionary modelState)
{
      var query = from state in modelState.Values
                  from error in state.Errors
                  select error.ErrorMessage;

      var errorList = query.ToList();
      return errorList;
}

The above method returns a list of validation errors.

Further Reading :

How to read all errors from ModelState in ASP.NET MVC

Upvotes: 39

james31rock
james31rock

Reputation: 2705

In case anyone wants to return the Name of the Model property for binding the error message in a strongly typed view.

List<ErrorResult> Errors = new List<ErrorResult>();
foreach (KeyValuePair<string, ModelState> modelStateDD in ViewData.ModelState)
{
    string key = modelStateDD.Key;
    ModelState modelState = modelStateDD.Value;

    foreach (ModelError error in modelState.Errors)
    {
        ErrorResult er = new ErrorResult();
        er.ErrorMessage = error.ErrorMessage;
        er.Field = key;
        Errors.Add(er);
    }
}

This way you can actually tie the error in with the field that threw the error.

Upvotes: 12

mmutilva
mmutilva

Reputation: 18994

Using LINQ:

IEnumerable<ModelError> allErrors = ModelState.Values.SelectMany(v => v.Errors);

Upvotes: 653

Alfred Severo
Alfred Severo

Reputation: 506

In your implementation you are missing static Class, this should be.

if (!ModelState.IsValid)
{
    var errors =  ModelStateErrorHandler.GetModelErrors(this.ModelState);
    return Json(new { errors });
}

rather

if (!ModelState.IsValid)
{
    var errors = ModelState.GetModelErrors();
    return Json(new { errors });
}

Upvotes: -1

CodeArtist
CodeArtist

Reputation: 5684

For just in case someone need it i made and use the following static class in my projects

Usage example:

if (!ModelState.IsValid)
{
    var errors = ModelState.GetModelErrors();
    return Json(new { errors });
}

Usings:

using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Web.Mvc;
using WebGrease.Css.Extensions;

Class:

public static class ModelStateErrorHandler
{
    /// <summary>
    /// Returns a Key/Value pair with all the errors in the model
    /// according to the data annotation properties.
    /// </summary>
    /// <param name="errDictionary"></param>
    /// <returns>
    /// Key: Name of the property
    /// Value: The error message returned from data annotation
    /// </returns>
    public static Dictionary<string, string> GetModelErrors(this ModelStateDictionary errDictionary)
    {
        var errors = new Dictionary<string, string>();
        errDictionary.Where(k => k.Value.Errors.Count > 0).ForEach(i =>
        {
            var er = string.Join(", ", i.Value.Errors.Select(e => e.ErrorMessage).ToArray());
            errors.Add(i.Key, er);
        });
        return errors;
    }

    public static string StringifyModelErrors(this ModelStateDictionary errDictionary)
    {
        var errorsBuilder = new StringBuilder();
        var errors = errDictionary.GetModelErrors();
        errors.ForEach(key => errorsBuilder.AppendFormat("{0}: {1} -", key.Key,key.Value));
        return errorsBuilder.ToString();
    }
}

Upvotes: 6

Dunc
Dunc

Reputation: 18922

Building on the LINQ verison, if you want to join all the error messages into one string:

string messages = string.Join("; ", ModelState.Values
                                        .SelectMany(x => x.Errors)
                                        .Select(x => x.ErrorMessage));

Upvotes: 236

Jason Dufair
Jason Dufair

Reputation: 671

In addition, ModelState.Values.ErrorMessage may be empty, but ModelState.Values.Exception.Message may indicate an error.

Upvotes: 3

Simon_Weaver
Simon_Weaver

Reputation: 145880

During debugging I find it useful to put a table at the bottom of each of my pages to show all ModelState errors.

<table class="model-state">
    @foreach (var item in ViewContext.ViewData.ModelState) 
    {
        if (item.Value.Errors.Any())
        { 
        <tr>
            <td><b>@item.Key</b></td>
            <td>@((item.Value == null || item.Value.Value == null) ? "<null>" : item.Value.Value.RawValue)</td>
            <td>@(string.Join("; ", item.Value.Errors.Select(x => x.ErrorMessage)))</td>
        </tr>
        }
    }
</table>

<style>
    table.model-state
    {
        border-color: #600;
        border-width: 0 0 1px 1px;
        border-style: solid;
        border-collapse: collapse;
        font-size: .8em;
        font-family: arial;
    }

    table.model-state td
    {
        border-color: #600;
        border-width: 1px 1px 0 0;
        border-style: solid;
        margin: 0;
        padding: .25em .75em;
        background-color: #FFC;
    }
 </style>

Upvotes: 21

Chris Marisic
Chris Marisic

Reputation: 33098

This is expanding upon the answer from @Dunc . See xml doc comments

// 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;            
    }
}

Upvotes: 4

Steve Lydford
Steve Lydford

Reputation: 428

Useful for passing array of error messages to View, perhaps via Json:

messageArray = this.ViewData.ModelState.Values.SelectMany(modelState => modelState.Errors, (modelState, error) => error.ErrorMessage).ToArray();

Upvotes: 4

Alan Macdonald
Alan Macdonald

Reputation: 1900

As I discovered having followed the advice in the answers given so far, you can get exceptions occuring without error messages being set, so to catch all problems you really need to get both the ErrorMessage and the Exception.

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

or as an extension method

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

}

Upvotes: 16

amiry jd
amiry jd

Reputation: 27575

And this works too:

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

Upvotes: 4

Oren Trutner
Oren Trutner

Reputation: 24208

foreach (ModelState modelState in ViewData.ModelState.Values) {
    foreach (ModelError error in modelState.Errors) {
        DoSomethingWith(error);
    }
}

See also How do I get the collection of Model State Errors in ASP.NET MVC?.

Upvotes: 591

Related Questions