Chapter 5: Validating Form Input

hozdaman · January 4th, 2012, 05:10 PM

Hi,

I am having issue getting the error message to come up for the email address. When its empty and I select "Post" no error message. Thanks.

Below is my code

Code:

@{
    Page.Title="Post Your Advertisement";
    if(IsPost){
        if(Request["title"].IsEmpty()){
            ModelState.AddError("title", "Please provide a title");
        }
        if(Request["title"].Length > 200){
            ModelState.AddError("title","Your title cannot exceed 200 characters");
        }
        if(Request["description"].IsEmpty()){
            ModelState.AddError("description", "You must provide a description");
        }
        if(Request["duration"].IsEmpty()){
            ModelState.AddError("duration", "Please choose a duration");
        }
        if(Request["price"].IsEmpty()){
            ModelState.AddError("price", "Please provide a price");
        }
        if(Request["price"].IsDecimal () && !Request["Price"].IsEmpty()){
            ModelState.AddError("price", "Please provide a valid number for the price");
        }
        if(Request["condition"].IsEmpty()){
            ModelState.AddError("condition", "Please state the condition of your item");
        }
        if(Request["email"].IsEmpty()){
            ModelState.AddError("email", "Please provide your email address");
        }
        if(!Request["email"].IsEmpty() && !Functions.IsValidEmail(Request["Email"])){
            ModelState.AddError("email", "Please provide a valid email address");
        }
        if(!ModelState.IsValid){
            ModelState.AddFormError("Please fix the errors below before submitting the form");
        }
    }
}

<form id=" ="post-advert" action="@Href("~/Sell")" method="post">
    <fieldset>
        <legend>Post Your Advertisement</legend>
        @Html.ValidationSummary(true)
        <div>
            <label for="title">Title</label>
        </div>
        <div>
            <input type="text" name="title" value="@Request["title"]" />
            @Html.ValidationMessage("title")
        </div>
        <div>
            <label for="description">Description</label>
        </div>
        <div>
            <textarea name="description">@Request["description"]</textarea>
            @Html.ValidationMessage("description")
        </div>
        <div>
            <label for="duration">Duration</label>
        </div>
        <div>
            <select name="duration">
                <option value="">--Choose One--</option>
                <option value="1" @Helpers.Selected("Duration","1")>1 Day</option>
                <option value="3" @Helpers.Selected("Duration","3")>3 Days</option>
                <option value="7" @Helpers.Selected("Duration","7")>7 Days</option>
                <option value="14" @Helpers.Selected("Duration","14")>14 Days</option>
            </select>
            @Html.ValidationMessage("duration")
        </div>
        <div>
            <label for="price">Price*</label>
        </div>
        <div>
            <input type="text" name="price" value="@Request["price"]" />
            @Html.ValidationMessage("price")
        </div>
        <div>
            <label for="condition">Condition</label>
        </div>
        <div>
            <input type="radio" name="condition" value="Fair" @Helpers.Checked("Condition","Fair") />Fair
            <input type="radio" name="condition" value="Good" @Helpers.Checked("Condition","Good") />Good
            <input type="radio" name="condition" value="As New" @Helpers.Checked("Condition","As New") />As New
            @Html.ValidationMessage("condition")
        </div>
        <div>
            <label for="email">Your Email Address</label>
        </div>
        <div>
            <input type="text" name="email" value="@Request["email"]" />
        </div>
        <div>
            <input type="submit" name="submit" value="Post" />
        </div>
    </fieldset>
</form>

Mike Brind · January 4th, 2012, 06:37 PM

You seem to have omitted @Html.ValidationMessage("email"), which is the placeholder for the email validation message. It should appear just under the following line of code:

<input type="text" name="email" value="@Request["email"]" />

jpjamie · January 5th, 2012, 04:52 PM

hozdaman thanks for posting your code above as it will help me figure out a better way to validate some of my TextAreas. I have a 16 question multiple choice online quiz which is validated for the answers, however there are 16 associated comment (TextArea) sections. I want to limit these TextAreas in case somebody enters with a cut and paste "...all work and no play makes Jack a dull boy..." thousands of times. If it CAN be done it WILL be done!

So, is there a better way than writing the code 16 below times (different field names of course)? All work and no play does make Jack a dull boy!

Code:

if(Request["Q1Comments"].Length > 200){
            ModelState.AddError("Q1Comments","Your comment cannot exceed 200 characters");
        }

Imar · January 5th, 2012, 04:56 PM

Hi there,

If all your controls are number sequentially, you can set up a for loop:

Code:

 
for (int i = 0; i < 16; i++)
{
  if(Request["Q" + i.ToString() + "Comments"].Length > 200)
  {
    ModelState.AddError("Q" + i.ToString() + "Comments","Your comment cannot exceed 200 characters");
  }
}

Alternatively, you can set up an array of field names and loop over that.

Hope this helps,
Imar

jpjamie · January 5th, 2012, 05:54 PM

Quote:

Originally Posted by Imar

Hi there,

If all your controls are number sequentially, you can set up a for loop:

Code:

 
for (int i = 0; i < 16; i++)
{
  if(Request["Q" + i.ToString() + "Comments"].Length > 200)
  {
    ModelState.AddError("Q" + i.ToString() + "Comments","Your comment cannot exceed 200 characters");
  }
}

Alternatively, you can set up an array of field names and loop over that.

Hope this helps,
Imar

Thanks Imar! Love this WebMatrix book!

Mike Brind · January 6th, 2012, 11:55 AM

Or, if all your controls start with or end with the same string in their name, you can use string.StartsWith or string.EndsWith in a foreach loop

Code:

foreach(string item in Request.Form){
    if(item.EndsWith("Comments")){
        if(Request[item].Length > 200){
            ModelState.AddError(item, "Less than 200 characters, please");
        }
    }
}

jpjamie · January 6th, 2012, 01:17 PM

Quote:

Originally Posted by Mike Brind

Or, if all your controls start with or end with the same string in their name, you can use string.StartsWith or string.EndsWith in a foreach loop

Code:

foreach(string item in Request.Form){
    if(item.EndsWith("Comments")){
        if(Request[item].Length > 200){
            ModelState.AddError(item, "Less than 200 characters, please");
        }
    }
}

Thanks! Will try this out. All of my question's comment TextAreas are named Q1Comments, Q2Comments, Q3Comments etc., so they "EndsWith" "Comments" so will try this! Will be interesting to see if the code "splits off" the "Q1", "Q2", "Q3" etc. and runs the logic.

snaebjorn · November 3rd, 2014, 03:30 PM

@{
Page.Title = "Post Your Advertisement";
if(IsPost){
if(HttpContext.Current.Request["title"].IsEmpty()){
ModelState.AddError("title", "Please provide a title");}
}
if(HttpContext.Current.Request["title"].Length > 200){
ModelState.AddError("title", "Your title cannot exceed 200 characters");
}
if(HttpContext.Current.Request["description"].IsEmpty()){
ModelState.AddError("description", "You must provide a description");
}
if(HttpContext.Current.Request["duration"].IsEmpty()){
ModelState.AddError("duration", "Please choose a duration");
}
if(HttpContext.Current.Request["price"].IsEmpty()){
ModelState.AddError("price", "You must provide price");
}
if(!HttpContext.Current.Request["price"].IsDecimal() && !HttpContext.Current.Request["price"].IsEmpty()){
ModelState.AddError("price", "Provide a valid number for the price");
}
if(HttpContext.Current.Request["condition"].IsEmpty()){
ModelState.AddError("condition", "State the condition for your item");
}
if(HttpContext.Current.Request["email"].IsEmpty()){
ModelState.AddError("email", "You must provide a valid email");
}
if(!ModelState.IsValid){
ModelState.AddFormError("Please fix the errors");
}
}
<body>
<form id="post-advert" action="@Href("~/Sell")" method="post" >
<fieldset>
<legend>Post Your Advertisement</legend>
@Html.ValidationSummary(true)
<div>
<label for="title">Title</label>
</div>
<div>
<input type="text" name="title" value="@Request["title"]" />
@Html.ValidationMessage("title")
</div>
<div>
<label for="description">Description</label>
</div>
<div>
<textarea name="description">@Request["description"]</textarea>
@Html.ValidationMessage("description")
</div>
<div>
<label for="duration">Duration</label>
</div>
<div>
<select name="duration">
<option value="">--Choose one</option>
<option value="1" @Helpers.Selected("Duration", "1")>1 Day</option>
<option value="3" @Helpers.Selected("Duration", "3")>3 Days</option>
<option value="7" @Helpers.Selected("Duration", "7")>7 Days</option>
<option value="14" @Helpers.Selected("Duration", "14")>14 Days</option>

</select>
@Html.ValidationMessage("duration")
</div>
<div>
<label for="price">Price</label>

</div>
<div>
<input type="text" name="price" value="@Request["price"]"/>
@Html.ValidationMessage("price")
</div>
<div>
<label for="condition">Price</label>

</div>
<div>
<input type="radio" name="condition" value="@Request["condition"]"
@Helpers.Checked("condition","Fair")/> Fair
<input type="radio" name="condition" value="Good"
@Helpers.Checked("condition", "Good")/>Good
<input type="radio" name="condition" value="As New"
@Helpers.Checked("condition", "As New")/>As New
@Html.ValidationMessage("condition")
</div>
<div>
<label for="email">Your Email Address</label>
</div>
<div>
<input type="text" name="email" value="@Request["email"]"/>
@Html.ValidationMessage("email")
</div>
<div>
<input type="submit" name="submit" value="Post" />
</div>
</fieldset>

</form>
</body>
@section footer{
This is a footer for the Sell page
}/>

It says that <Option value="1" @Helpers.Selected("Duration", "1")>1 day</option> is out of context.

Imar · November 3rd, 2014, 03:45 PM

Did you add the Helpers to your project?

Imar

snaebjorn · November 3rd, 2014, 04:06 PM

I was following your example from your book (I had to make some changes from your book i.e. if(HttpContext.Current.Request["email"].IsEmpty()){
ModelState.AddError("email", "You must provide a valid email");
} which isn't in the book), and I keep getting context errors. My request objects work, but not my function (@Helpers.Selected) and I think I'll get the same error with the Helpers.Checked function.