Question

here is the code:

HTML:

<textarea data-bind="value: MyText">
    Hello world
    line 2
    line 3
</textarea>   

JS:

var viewModel = 
{
    MyText : ko.observable()  
};
ko.applyBindings(viewModel);   

http://jsfiddle.net/HSfuq/

Textarea becomes empty, because of ko.observable(), but how can I save existing value in textarea?

I have big multiline document in textarea (from database), and I want to edit it with features of Knockoutjs.

Thanks.

Answer 1

Don’t extract the text from HTML, just make your view model like this:

var viewModel = {

    MyText : ko.observable("I'm the data from the server")  

};

ko.applyBindings(viewModel);    

http://jsfiddle.net/HSfuq/1/
I would prefer the first method.

Or you can extract the text from the html like this, if you must do so:

HTML:

<textarea data-bind="value: MyText" id='textareaID'>
    Hello world
    line 2
    line 3
</textarea>  

JS:

//using jQuery, but you could do this otherwise as well 
var texareaText = $('#textareaID').text();
var viewModel = {

    MyText : ko.observable( texareaText )  

};

ko.applyBindings(viewModel);  

http://jsfiddle.net/HSfuq/2/

Or use JSON serialization (any way you like, return JSON(yourDataIncludingMultiLineText); from MVC controller action, or a serializer library like Newtonsoft JSON.net http://nuget.org/List/Packages/Newtonsoft.Json) to serialize the multi line text.