KnockoutJS - index of print iteration as input name

I am trying to create my first KnockoutJS form view combined with Spring MVC binding @ModelAttribute

.

• Data is loaded via Ajax and populated with KnockoutJS
• Data is added via KnockoutJS
• Data is removed on top of Ajax and KnockoutJS
• The data will be saved with a normal POST to the Spring MVC controller.

In order to bind form input to Spring MVC controller, I need an iteration index from KnockoutJS. So I tried the following:

But the values ​​from my database are never linked the way they are when I link them to data-bind='value: key'

. Can you help me with the error?

JSP:

<form:form modelAttribute="configurationHelper" action="/saveConfigurationList.htm" method="POST" id="configuration-form" class="form-inline">
    <tbody data-bind="foreach: configurations">
        <tr>
            <td>
                // this is working
                <input data-bind='value: key' class="form-control input-sm" type="text"/>
                // this is not working
                <input data-bind='attr:{value: key, name:configurationHelper.configurations[$index].key' class="form-control input-sm" type="text"/> 
            </td>
            <td>
                <a href='#' data-bind='click: $root.removeConfiguration' class="ordinary-tooltip" title='<spring:message code="general.delete"/>'>
                    <i class="fa fa-lg fa-trash-o "></i>
                </a>
            </td>
         </tr>
    </tbody>
</form:form>

      

        
        
        
      

    

ModelView:

function ConfigurationViewModel() {
    var self = this;
    self.configurations = ko.observableArray([]);

    self.loadConfigurations = function() {
        $.ajax({
            type : "POST",
            url : "/loadConfigurationList.htm",
            success : function(response) {
                var responseArray = JSON.parse(response);
                var mappedConfigurations = $.map(responseArray.configurations, function(configuration) {
                    return new Configuration(configuration);
                });
                self.configurations(mappedConfigurations);
            },
            error : function(e) {
                alert('Error: ' + e.status);
            }
        });
    }

    self.saveConfigurationList = function() {
        $("#configuration-form").submit();
    }

    self.addConfiguration = function() {
            self.configurations.push({
                id: 0,
                key: "",
                value: "",
        });
    };

    self.removeConfiguration = function(configuration) {
        if(confirm(springMessageGeneralDeleteReally)){
            $.ajax({
                type : "POST",
                url : "/deleteConfiguration.htm",
                data: {"configurationId": configuration.id},
                success : function(response) {
                    self.configurations.remove(configuration);
                },
                error : function(e) {
                    alert('Error: ' + e.status);
                }
            });
        }
    };
}


function Configuration(data) {
    this.id = ko.observable(data.id);
    this.key = ko.observable(data.key);
    this.value = ko.observable(data.value);
}

      

        
        
        
      

    

Summary:

• The knockout should only bind values ​​(AJAX loaded) to the inputs and display the correct input name. (for binding input value to Spring MVC controller)
• configurationHelper
  
  is a request parameter and shouldn't bother knockout. It is only available for list binding configurationHelper.configurations
  
  to Spring MVC.

The following form is bound to the Spring MVC controller:

<form:form modelAttribute="configurationHelper" action="/leina16/configuration/saveConfigurationList.htm" method="POST" id="configuration-form" class="form-inline">
    <form:input path="configurations[0].key" class="form-control input-sm"/>
</form:form>

      

        
        
        
      

    

Now I want to expand inputs with Knockout JS, so I need at least an attribute data-bind

and also foreach: $index

from knockout:

<tbody data-bind="foreach: configurations">
    <input data-bind='attr:{value: key, name:"configurations[$index].key}' class="form-control input-sm" type="text"/>
</tbody>

      

        
        
        
      

    

But the above is not tied to a Spring MVC controller method and the values ​​are not populated.