题
I have a View Model that has a Byte[] property and it is required at the moment a user creates a new item, here is my model:
https://stackoverflow.com/questions/23687420
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Russianpublic class ClassViewModel2
{
public int ClassId { get; set; }
[Required(ErrorMessage = "This field is required to create a Class")]
public string Name { get; set; }
[Required(ErrorMessage = "This field is required to create a Class")]
public string Description { get; set; }
[Required(ErrorMessage = "This field is required to create a Class")]
public byte[] ThumbNail { get; set; }
[Required(ErrorMessage = "This field is required to create a Class")]
public byte[] MainImage { get; set; }
}
but if the Byte[] is null it will continue creating the item anyway, it works fine with the other properties so I am not sure how to include a validation for this.
This is my Edit Controler:
[HttpPost]
[ValidateInput(false)]
[Authorize(Roles = Constants.Roles.Admins)]
public virtual ActionResult Edit(ClassViewModel classdetail, HttpPostedFileBase fmainimage,
HttpPostedFileBase fthumbnail)
{
UserProfile up = GetUserProfile();
if (up != null)
{
if (ModelState.IsValid)
{
var mclass =
(from c in _db.Classes where c.ClassId == classdetail.ClassId select c).FirstOrDefault() ??
new Class();
Mapper.Map(classdetail, mclass, typeof(ClassViewModel), typeof(Class));
var mclass2 =
(from c in _db.Classes where c.ClassId == classdetail.ClassId select c).FirstOrDefault() ??
new Class();
Mapper.Map(classdetail, mclass2, typeof(ClassViewModel2), typeof(Class));
if (fmainimage != null)
{
int length = fmainimage.ContentLength;
mclass.MainImage = new byte[length];
fmainimage.InputStream.Read(mclass.MainImage, 0, length);
mclass2.MainImage = new byte[length];
fmainimage.InputStream.Read(mclass2.MainImage, 0, length);
}
if (fthumbnail != null)
{
int length1 = fthumbnail.ContentLength;
mclass.ThumbNail = new byte[length1];
fthumbnail.InputStream.Read(mclass.ThumbNail, 0, length1);
mclass2.ThumbNail = new byte[length1];
fthumbnail.InputStream.Read(mclass2.ThumbNail, 0, length1);
}
if (classdetail.ClassId == 0)
{
//assign default if not assigned
Studio currentstudio = _db.Studios.Find(up.StudioId);
currentstudio.Classes.Add(mclass2);
}
else
{
_db.Entry(mclass).State = EntityState.Modified;
}
_db.SaveChanges();
return RedirectToAction(Actions.Details(mclass.ClassId));
}
}
classdetail.Trainers = (from t in _db.Trainers where t.Studio.StudioId == up.StudioId select t).ToList()
.Select(
tr =>
new SelectListItem
{
Value
=
tr
.TrainerId
.ToString
(),
Text
=
tr
.FirstName +
" " +
tr
.LastName
});
return View(classdetail);
}
and this is in my view:
@using (Html.BeginForm(MVC.Class.Edit(), FormMethod.Post, new { @class = "form label-inline", name = "iform", enctype = "multipart/form-data" }))
{
@Html.HiddenFor(model => model.ClassId)
<div class="formSep">
<label class="req">Name</label>
<span style="color:red">@Html.ValidationMessageFor(model => model.Name)</span>
@Html.EditorFor(model => model.Name, new { @class = "medium" })
</div>
<div class="formSep">
<label class="req">Description</label>
<span style="color:red">@Html.ValidationMessageFor(model => model.Description)</span>
@Html.TextAreaFor(model => model.Description, new { style = "width: 420px; height: 6em;" })
</div>
<div class="formSep">
<label class="req">Instructional Video Description</label>
<span style="color:red">@Html.ValidationMessageFor(model => model.InstructionalDescription)</span>
@Html.TextAreaFor(model => model.InstructionalDescription, new { style = "width: 420px; height: 6em;" })
</div>
if(Model.ClassId == 0){
<div class="formSep">
@Html.CheckBoxFor(model => model.IsRewatchable, new { style = "display:inline;" })
<label style="display: inline;" class=""> The videos in the class can be watched any number of times</label>
</div>
}
else{
<div class="formSep" style="display:none">
@Html.CheckBoxFor(model => model.IsRewatchable, new { style = "display:inline;" })
<label style="display: inline;" class=""> The videos in the class can be watched any number of times</label>
</div>
}
if (Model.ClassId == 0) {
<div class="formSep">
@Html.CheckBoxFor(model => model.IsAttendable, new { style = "display:inline;" })
<label style="display: inline;" class=""> Attendance is recorded for this class</label>
</div>
}
else
{
<div class="formSep" style="display:none">
@Html.CheckBoxFor(model => model.IsAttendable, new { style = "display:inline;" })
<label style="display: inline;" class=""> Attendance is recorded for this class</label>
</div>
}
<div class="formSep">
<label class="req">Class Image</label>
<span style="color:red">@Html.ValidationMessageFor(model => model.MainImage)</span>
<input type="file" name="fmainimage" id="fmainimage" /><br />
@if (Model.ClassId != 0)
{
if (Model.MainImage != null)
{
<img src="@Url.Action(MVC.Class.GetMainImage(Model.ClassId))"/>
}
else
{
<text>No Main Image Exists</text>
}
}
</div>
<div class="formSep">
<label class="req">Thumbnail</label>
<span style="color:red">@Html.ValidationMessageFor(model => model.ThumbNail)</span>
<input type="file" name="fthumbnail" id="fthumbnail" /><br />
@if (Model.ClassId != 0)
{
if (Model.ThumbNail != null)
{
<img src="@Url.Action(MVC.Class.GetThumbnail(Model.ClassId))"/>
}
else
{
<text>No Thumbnail Exists</text>
}
}
</div>
<div class="formSep">
<label class="req">Trainer</label>
<span style="color:red">@Html.ValidationMessageFor(model => model.Trainer)</span>
@Html.DropDownListFor(model => model.TrainerId, new SelectList(Model.Trainers, "value", "text", @Model.TrainerId))
</div>
<div class="formSep">
<button type="submit" class="button-small-theme rounded3">SAVE</button> <a href="@Url.Action(MVC.Class.Details(Model.ClassId))" class="button-small-cancel rounded" style="padding: 12px 10px 9px;">CANCEL</a>
</div>
}
If the ID of the item is 0 it will use the same edit View but it will create a new Item
解决方案
Well you are saving the model even if your byte[] is null, the Model.IsValid wont catch the "error". You should redirect back the view() it the byte[] is null.
Add this before your save.
if (fthumbnail == null || fthumbnail == null)
{
ModelState.AddModelError("_FORM", "Your little error message to the user.");
return View(classdetail);
}
其他提示
Create your own data validations by overriding the IsValid Method
public class MyAmazingValidations : RequiredAttribute
{
public override bool IsValid(object value)
{
bool isValid = base.IsValid(value);
if(isValid)
{
ICollection collection = value as ICollection;
if(collection != null)
{
isValid = collection.Count != 0;
}
}
return isValid;
}
}
then go to ur model and decorate your property :
[MyAmazingValidations (ErrorMessage="You made a big mistake right now!")]
public byte[] someProperty{ get; set; }
