/// <summary>
/// Clears the validation messages and exceptions associated with a model property,
/// making the value in that property valid.
/// </summary>
/// <param name="modelState">ModelState object from which the model property will be removed, and thus be considered as valid.</param>
/// <param name="expression">Expression tree that goes to the property that should be made valid.</param>
public static void ClearPropertyErrors(this ModelStateDictionary modelState, Expression <Func <object> > expression)
{
var propertyInfo = MemberExpressionHelper.GetPropertyInfo(expression);
if (modelState.ContainsKey(propertyInfo.Name))
{
modelState[propertyInfo.Name].Errors.Clear();
}
}
public static string GetRegularExpressionPattern <TModel>(Expression <Func <TModel, Object> > expression)
{
var propertyInfo = MemberExpressionHelper.GetPropertyInfo(expression);
var regularExpressionAttribute = propertyInfo.GetCustomAttributes(typeof(RegularExpressionAttribute), true).Cast <RegularExpressionAttribute>().FirstOrDefault();
if (regularExpressionAttribute == null)
{
throw new Exception("Expression member does not have a RegularExpressionAttribute");
}
return(regularExpressionAttribute.Pattern);
}
public static string GetDisplayName <TModel>(Expression <Func <TModel, Object> > expression)
{
var propertyInfo = MemberExpressionHelper.GetPropertyInfo(expression);
var displayAttribute = propertyInfo.GetCustomAttributes(typeof(DisplayAttribute), true).Cast <DisplayAttribute>().FirstOrDefault();
if (displayAttribute == null)
{
return(propertyInfo.Name);
}
return(displayAttribute.Name);
}
/// <summary>
/// Returns the ModelState object associated with a model property.
/// </summary>
/// <param name="modelState">ModelStateDictionary that contains validation messages of the model.</param>
/// <param name="expression">Expression tree that goes to the property of the model, for which to return the associated ModelState.</param>
/// <returns>
/// Returns the ModelState associated with the property represented by the expression tree.
/// If there is no ModelState associated, then returns null.
/// </returns>
public static ModelErrorCollection GetPropertyErrors(this ModelStateDictionary modelState, Expression <Func <object> > expression)
{
var propertyInfo = MemberExpressionHelper.GetPropertyInfo(expression);
var result = modelState[propertyInfo.Name];
if (result == null)
{
return(null);
}
return(result.Errors);
}
/// <summary>
/// Add a new validation message to the collection of messages and exceptions associated with the given model property.
/// </summary>
/// <param name="modelState">ModelState objeto to add the validation message to.</param>
/// <param name="expression">Expression tree that goes to the property that is not valid.</param>
/// <param name="errorMessage">Validation message to associate with the property.</param>
public static void AddModelError(this ModelStateDictionary modelState, Expression <Func <object> > expression, [Localizable(true)] string errorMessage)
{
// todo: this method should accept a resource name, instead of an error message.
var propertyInfo = MemberExpressionHelper.GetPropertyInfo(expression);
if (errorMessage.Contains("{0}"))
{
var displayAttribute = propertyInfo.GetCustomAttributes(typeof(DisplayAttribute), true).Cast <DisplayAttribute>().FirstOrDefault();
var propertyDisplay = displayAttribute != null ? displayAttribute.Name : propertyInfo.Name;
errorMessage = string.Format(errorMessage, propertyDisplay);
}
modelState.AddModelError(propertyInfo.Name, errorMessage);
}
public static void AddModelError <TModel>(
this ModelStateDictionary modelState,
Expression <Func <TModel, object> > expression,
string errorMessage)
{
// todo: this method should accept a resource name, instead of an error message.
var propertyInfo = MemberExpressionHelper.GetPropertyInfo(expression);
var propertyDisplay = MemberExpressionHelper.GetPropertyDisplayName(propertyInfo);
errorMessage = string.Format(errorMessage, propertyDisplay);
modelState.AddModelError(propertyInfo.Name, errorMessage);
}
public static MvcHtmlString EnumDisplayFor <TModel, TValue>(this HtmlHelper <TModel> html, Expression <Func <TModel, TValue> > expression)
where TModel : class
{
var propertyInfo = MemberExpressionHelper.GetPropertyInfo(expression);
Type enumType;
if (propertyInfo.PropertyType.IsEnum)
{
enumType = propertyInfo.PropertyType;
}
else
{
var attributes = propertyInfo.GetCustomAttributes(typeof(EnumDataTypeAttribute), true);
if (attributes.Length == 0)
{
throw new Exception("cannot resolve enum type");
}
enumType = ((EnumDataTypeAttribute)attributes[0]).EnumType;
if (enumType == null)
{
throw new Exception("cannot resolve enum type");
}
}
var model = html.ViewData.Model;
if (model == null)
{
return(new MvcHtmlString(""));
}
var modelValue = propertyInfo.GetValue(model, null);
if (modelValue == null)
{
return(new MvcHtmlString(""));
}
return(new MvcHtmlString(EnumHelper.GetText((int)modelValue, enumType)));
}
/// <summary>
/// Remove the validation messages and exceptions associated with a model property,
/// making the value in that property valid.
/// </summary>
/// <param name="modelState">ModelState object from which the model property will be removed, and thus be considered as valid.</param>
/// <param name="expression">Expression tree that goes to the property that should be made valid.</param>
/// <param name="hasPrefix">Whether the model-state entry name has a prefix or not.</param>
public static void Remove(this ModelStateDictionary modelState, Expression <Func <object> > expression, bool hasPrefix = false)
{
var propertyInfo = MemberExpressionHelper.GetPropertyInfo(expression);
if (hasPrefix)
{
var name = '.' + propertyInfo.Name;
foreach (var modelStateItem in modelState.ToArray())
{
if (modelStateItem.Key.EndsWith(name))
{
modelState.Remove(modelStateItem.Key);
}
}
}
else
{
modelState.Remove(propertyInfo.Name);
}
}