line breaks in textarea used in a MVC C# website app
Asked Answered
S

10

29

I'm using ASP.net MVC C# in Visual Studio Web Dev. I have a couple of textareas which are populated with data and then updated to a database record.

Is it possible to have line breaks saved when a record is updated to the database? I currently view the data on the homepage, but at the moment if someone writes couple of paragraphs (including line breaks) the formatting will be lost.

If this isn't possible no problem, but just wanted to ask if it is. Thanks.

The code on the View page looks like this:

<div class="editor-field">
        @Html.TextAreaFor(model => model.para1, new { cols = 75, @rows = 5 })
        @Html.ValidationMessageFor(model => model.para1)
</div>

I then have a button that submits the form.

The Controller code that handles the submission looks like this:

[HttpPost]
    public ActionResult Update(Data data)
    {
        if (ModelState.IsValid)
        {
            data.ID = 1; //EF need to know which row to update in the database.
            db.Entry(data).State = EntityState.Modified;
            db.SaveChanges();
            return RedirectToAction("Index", "Home");
        }
        return View(data);
    }

and the Model code for the database looks like this:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Data.Entity;
using System.ComponentModel.DataAnnotations;

namespace DFAccountancy.Models
{
    public class Data
    {
        [DataType(DataType.MultilineText)]
        public int ID { get; set; }
        public string para1 { get; set; }
        public string para2 { get; set; }
    }

    public class DataDBContext : DbContext
    {
        public DbSet<Data> Data { get; set; }
    }
}

===========================================

the Homepage code

@model IEnumerable<DFAccountancy.Models.Data>

@{
    ViewBag.Title = "Index";
}

<h2>
    DF Accountancy
</h2>
<div>

<fieldset>
<legend>About us</legend>

@foreach (data in Model)
{

<table>
    <tr>
        <td rowspan="2" width="50%">
            <b>
                Suspendisse lectus massa, feugiat at cursus ac, sollicitudin a metus.     Quisque adipiscing commodo sem vitae eleifend. 
            Maecenas ante risus, hendrerit ac tempor et, feugiat eu sapien. Sed sem massa, sodales a varius sit amet, porta in 
            turpis. Duis ullamcorper magna sed risus lobortis luctus. Quisque volutpat enim ut erat tristique sit amet posuere 
            sem ullamcorper. Nulla consequat lectus in sapien sagittis cursus. Quisque elit augue, luctus sed semper non, fringilla 
            sed quam. Pellentesque habitant morbi tristique senectus et netus et malesuada fames ac turpis egestas. Fusce vitae 
            augue quis nisi tincidunt ullamcorper. Duis posuere ultricies turpis at dictum. Vivamus at odio eros. Nunc orci 
            lectus, ornare non tincidunt sed, venenatis id lorem. Nulla ullamcorper, leo quis pellentesque sollicitudin, dui 
            libero vehicula lectus, lobortis consequat orci dui in augue. Ut gravida enim convallis sem luctus sit amet eleifend 
            lorem malesuada. Suspendisse in augue diam, eu laoreet diam.
            </b>
            </td>
            <td>
                <div class="display-field">
                    @Html.Raw(data.para1.Replace(Environment.NewLine, "<br/>"))
                </div>
            </td>
        </tr>
        <tr>    
            <td>
                <div class="display-field">
                    @Html.Raw(data.para2.Replace(Environment.NewLine, "<br/>"))
                </div>
            </td>
        </tr>
</table>
}

        </fieldset>
</div>

==========================================

The full Update View page code

@model DFAccountancy.Models.Data

@{
    ViewBag.Title = "Update";
    }



<h2>Update</h2>

<script src="@Url.Content("~/Scripts/jquery.validate.min.js")" type="text/javascript">    </script>
<script src="@Url.Content("~/Scripts/jquery.validate.unobtrusive.min.js")" type="text/javascript"></script>

<script type="text/javascript">
    $(function () { $("#cl_button1").click(function () { $("#para1").val(""); }); });
    $(function () { $("#cl_button2").click(function () { $("#para2").val(""); }); });
</script>

@using (Html.BeginForm()) {
@Html.ValidationSummary(true)
<fieldset>
    <legend>Data</legend>

    <div class="editor-label">
        @Html.LabelFor(model => model.para1)
    </div>
    <div class="editor-field">
        @Html.TextAreaFor(model => model.para1, new { cols = 75, @rows = 5 })
        @Html.ValidationMessageFor(model => model.para1)
        <input id="cl_button1" type="button" value="Clear Paragraph" />
    </div>

    <div class="editor-label">
        @Html.LabelFor(model => model.para2)
    </div>
    <div class="editor-field">
        @Html.TextAreaFor(model => model.para2, new { cols = 75, @rows = 5 })
        @Html.ValidationMessageFor(model => model.para2)
        <input id="cl_button2" type="button" value="Clear Paragraph" />
    </div>



    <p>
        <input type="submit" value="Update" />
        <input type="reset" value="Re-Set to begining" />
    </p>

</fieldset>
}

<div>
    @Html.ActionLink("Back to List", "Index")
</div>
Sylvestersylvia answered 23/3, 2012 at 17:46 Comment(3)
Can you tell if the formatting is present in the database and just isn't visually represented when displaying the data?Commendam
not sure how to check that, I've just added <pre> tags round the part that displays the data from the database, and that "sort" of works, however the top line of text is pushed over to the right, so it isn't quite as expected.Sylvestersylvia
Does this answer your question? Replace line break characters with <br /> in ASP.NET MVC Razor viewHalutz
A
45

When displaying the field as html, it will not include line breaks since they are treated as spaces in html markup. You could replace them with <br/>. It would look something like this:

<div class="display-field">
   @Html.Raw(Model.para1.Replace(Environment.NewLine, "<br/>"))
</div>

Or you could display it as preformatted text, which will preserve white space:

<div class="display-field">
    <pre>
        @Model.para1
    </pre>
</div>

Update If your model is IEnumerable<T>:

@foreach (var data in Model)
{
    <div class="display-field">
       @Html.Raw(data.para1.Replace(Environment.NewLine, "<br/>"))
    </div>
}

or

@foreach (var data in Model)
{
    <div class="display-field">
        <pre>
            @data.para1
        </pre>
    </div>
}
Amendatory answered 23/3, 2012 at 17:50 Comment(15)
I thought he was asking about posting the data in the textarea. Do the linebreaks get lost? I don't think they do. Maybe I misunderstood the question.Handrail
I don't see anything that's stripping line breaks server side, so I assumed he meant displaying the database value.Amendatory
Hi, if possible, I want the text in the textarea to keep the formatting (i.e. carriage returns or line breaks, whichever they are called) so when I display that text later on (on the homepage as it happens) it has all the line breaks that were originally entered.Sylvestersylvia
Thank you jrummell, I've tried entering your example above, and it works on the update page, but when I attempt to display it on the homeepage it doesn't recognise "para1". I've added the full homepage code and update code above to see if that helps. Many thanks.Sylvestersylvia
What do you mean by it doesn't recognise "para1"?Amendatory
Apologies, it meant it underlines "para1" in red when in Visual Studio, then when I load the site it gives an error: zen87038.zen.co.uk/image/error.jpgSylvestersylvia
Your model is an IEnumerable<T> so you need to reference the current item, not the collection.Amendatory
may I ask for some assistance doing that? sorry, not got much clue :-(Sylvestersylvia
Apologies for delay, I've been away and unable to test. I've got another error: "Compiler Error Message: CS0230: Type and identifier are both required in a foreach statement"Sylvestersylvia
Screenie of the error is here: zen87038.zen.co.uk/dl/latest_error.jpg and I've updated the main code above to include your examples.Sylvestersylvia
@foreach (var data in Model)Amendatory
-1 Sorry - but as an experienced user like yourself you should really not suggest using the Replace newline with <br/> - This can cause more issues down the line. The use of <pre> with those extra lines causes extra lines in the HTML - it must be <pre>@content</pre> But that is a minor thing as using <pre> is the correct way to disapply pre formatted text. Its a small issue with pre but the main concern is using the replace newline with RAW and all that. Its just not how it should be done using ASP.MVC - that is bad practice borrowed from Classic ASP. HTML or TEXT- not both at once.Hyacinthia
Worse still this is a major vulnerability waiting to happen in your first example. I could insert <script> tags in your paragraph and get upgraded to unencoded Raw output inside a lovely div.Erdei
Can't please everyone :). This is a trivial example. No one should copy/paste anything from this site without fully understanding how it will impact their application.Amendatory
@Amendatory : I used ur trick but it gets annoying when anyone used to type any scripts code like <script> alert("hi") </script>Layer
H
9

Don't manipulate the data at all. When you display it just wrap it in <pre></pre>

Example: <pre>@Model.Data</pre>

This will preserve the carriage returns

Hormuz answered 16/7, 2012 at 16:11 Comment(2)
the last comment the OP made (on March 23rd) indicates that the OP already tried this. Welcome to SO, make sure you read the whole question and comments before posting an answer. (I'm guilty sometimes too)Ilarrold
I agree with this answer! The problem is the OP is not saving the data correctly or something is causing another problem. Like stylesheet resetting (another bunch of junk) Using all these hackish fixes can cause such abnormal behavior. This deserved a +1 regardless of the problem the OP was having! It is called good codding practise! This solved my problem exactly!Hyacinthia
G
7

Here's what I ended up doing which I think is basically the same as the <pre> tag but without the ugly bootstrap formatting (i.e. border, off white back-ground color, weird font style, etc)

CSS:

.multi-line{
   white-space: pre-wrap;
}

View:

<div class="multi-line">@Html.DisplayFor(model => model.Description)</div>
<div class="multi-line">@data.para</div>

Make sure there are no spaces between your div element and your html helper or those will show up too as someone else mentioned in the above answers with the <pre> tag.

Gober answered 25/10, 2015 at 21:18 Comment(0)
A
4

Pre works fine, BUT it takes some "odd" formatting.

    <pre>
        @data.para1
    </pre>

This sort of works, Except it indents the first line by the 8 spaces ahead of the @ (not right justified as it might appear at a glance)

    <pre>
@data.para1
    </pre>

This works well, but still has some stray returns.

<pre>@data.para1</pre>

This seems to be just right.

Adumbrate answered 3/3, 2014 at 20:29 Comment(2)
Excellent answer... and the font family and other formatting seems to go all wonky too. There's got to be a better way than this hurdle race down the rabbit hole. So annoying for something so fundamental. I've been looking at wysiwyg editors and the like all night when all I want are some paragraph tags and hyperlinks/img links to be visible.Gober
This was a classic, we had a perverted p tag with whitespace set to pre-wrap, but couldn't spot that we were using the first form in your example instead of the third form, giving us massive indentation on the first sentence only. Doh!Erdei
C
3

I don't know that it matters when saving the data - I assume it's just used for choosing the visualization of the member, but try moving your MultiLineText attribute to the string fields:

public class Data
{
    public int ID { get; set; }
    [DataType(DataType.MultilineText)]
    public string para1 { get; set; }
    [DataType(DataType.MultilineText)]
    public string para2 { get; set; }
}
Commendam answered 23/3, 2012 at 17:51 Comment(2)
Thank you for this, tried changing the code in the model and sadly it didn't work.Sylvestersylvia
@Sylvestersylvia did you use @HtmlDisaplyFor, @TextAreaFor , @EditorFor ??Hyacinthia
P
3

The linebreak inside a textbox is CrLf so the content is not populated to a textbox the next time they will seems to disapper. However if you look into the HTML source you will find that they exist.

But because a line break isn't equal to a <br/> it will be a bit confusing.

So what people are doing is to replace the CrLf to HTML BR like this:

string ContentToDatabase = input.replace(Environment.NewLine, "<br/>")

If you open the same content in the textarea again you will see <br/> insteed of linebreaks, so you have to convert it back.

string contentToEdit = fromDatabase.replace("<br/>",Environment.NewLine)
Patricepatrich answered 23/3, 2012 at 17:56 Comment(4)
thanks for this, would you mind offering some assistance on where abouts in my code I should be adding this? I'm still very new to all this and don't understand much of it yet.Sylvestersylvia
I*f I wanted to save <br/> to be displayed as HTML then that is how it should be saved to DB. Doing this hackish shiet is really bad codding practise! It does my head in when ppl try to solve a problem caused by a problem somewhere else. <br/> Is HTML and \n is NewLine - If I wanted to edit that in a separate program I would have to use this hack again. ITs baloney hacking and bad habbit. It just takes a few minutes to rethink what actually needs to happen. IOU -1Hyacinthia
No, @ppumkin this is in fact the only correct answer to the OP. This will save <br/> to the DB. It would only need to be converted back if you OP needed it to be editable in a textarea again. Yes, it's hackish, but sometimes hacks are the only feasible solution. As far as I can tell the only other method to allow HTML editing in a textarea would be to use a 3rd party plugin such as TinyMCE, which to integrate and test takes several hours. All to allow for a couple of HTML line-breaks! That would be like using a bazooka to swat a fly.Congratulatory
The front end should insert the br not the backend. Causing side effects isn't great. If the front end is tinymce and HTML it saves like that as it's expected. If not then no br. That is why tinymce and similar were created. To keep things consistent.Hyacinthia
H
0

Your problem probably isn't in the textarea. When displaying the input back on the home page, are you doing it within pre tags? If not, line breaks and formatting are ignored.

Honebein answered 23/3, 2012 at 17:52 Comment(1)
Hi there, thanks, no, I hadn't used pre tags, but I've since tried that and whilst it does allow for the line breaks / carriage returns it does seem to screw with the formatting a bit, including leaving the first line of text way over to the right of the div.Sylvestersylvia
E
0

I have run into a similar situation with this, needing to be able to add an entire article into a database from MVC3 and text areas. There are many ways you could go about this, but the simplest I've found is to turn off the ValidateInput (do NOT do this if you are opening up this to the public...this could cause cross site scripting and all sorts of nasties, make sure you validate the users).

    [HttpPost]
    [AuthRole(Role = "Administrator")]  //Created Validataion so inaccessible from outside
    [ValidateInput(false)]      
    public ActionResult Update(Data data)       
    {       
        if (ModelState.IsValid)       
        {       
            data.ID = 1; //EF need to know which row to update in the database.       
            db.Entry(data).State = EntityState.Modified;       
            db.SaveChanges();       
            return RedirectToAction("Index", "Home");       
        }       
        return View(data);       
    }    

If you put a breakpoint in the data, you should see the newline's character ('\r\n') within VStudio. You can this replace that particular character with whatever you'd like (I'd suggest Environment.Newline if this isn't posting back to HTML).

                data.dataString = dataString.Replace(@"\r\n", Environment.Newline);
                //Or change Newline to "<br />" if posting to HTML
Exactitude answered 23/3, 2012 at 19:0 Comment(4)
Thank you Brenton. This didn't seem to work though, the AuthRole part was underlined in red in Visual Web Developer. Maybe I haven't added a "using" reference at the top that is needed?Sylvestersylvia
Sorry, that's a custom attribute. You could easily just use the [Authorize] attribute.Exactitude
Thank you, I've amended and it seems to like the AuthRole part now. Regarding this bit: "If you put a breakpoint in the data" where abouts should I put this? currently I've got it just above: "return RedirectToAction("Index", "Home");" - also, for some reason, when I click "update" now, it returns me to the logon page ("localhost:53559/Admin/LogOn") rather than back to the homepage...Sylvestersylvia
This is even more shocking solution... What if I wanted to display line breaks in HTML but the actual text was used as javascript for tracking or something. Javascript does not understand <br/> - I need to say this because its really bad what you guys are coming up with here.Hyacinthia
A
0
public class YourClass
{
    public int Id { get; set; }

    [DataType(DataType.MultilineText)]
    public string paragraph { get; set; }
}

@Html.TextAreaFor(m => m.paragraph, new { @class = "form-control", @rows = 5 })
Abbreviation answered 26/4, 2016 at 9:52 Comment(1)
Please provide some explanation in addition to the code.Memorandum
H
0

If anybody wants another approach, here is a css solution which worked for me.

Add the css property:

white-space: pre-line;

This style will preserve line breaks and spaces from your textarea field when you display them in your view. It is safer than using @html.Raw() to manipulate the output as it does not interpret the content as HTML

Hawn answered 15/12, 2023 at 13:42 Comment(0)

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