How to declare a local variable in Razor?

问题:

I am developing a web application in asp.net mvc 3. I am very new to it. In a view using razor, I'd like to declare some local variables and use it across the entire page. How can this be done?

It seems rather trivial to be able to do the following action:

@bool isUserConnected = string.IsNullOrEmpty(Model.CreatorFullName);
@if (isUserConnected)
{ // meaning that the viewing user has not been saved
    <div>
        <div> click to join us </div>
        <a id="login" href="javascript:void(0);" style="display: inline; ">join</a>
    </div>
}

But this doesn't work. Is this possible?

回答1:

I think you were pretty close, try this:

@{bool isUserConnected = string.IsNullOrEmpty(Model.CreatorFullName);}
@if (isUserConnected)
{ // meaning that the viewing user has not been saved so continue
    <div>
        <div> click to join us </div>
        <a id="login" href="javascript:void(0);" style="display: inline; ">join here</a>
    </div>
}

回答2:

I think the variable should be in the same block:

@{bool isUserConnected = string.IsNullOrEmpty(Model.CreatorFullName);
    if (isUserConnected)
    { // meaning that the viewing user has not been saved
        <div>
            <div> click to join us </div>
            <a id="login" href="javascript:void(0);" style="display: inline; ">join</a>
        </div>
    }
    }

回答3:

You can also use:

@if(string.IsNullOrEmpty(Model.CreatorFullName))
{
...your code...
}

No need for a variable in the code

回答4:

If you're looking for a int variable, one that increments as the code loops, you can use something like this:

@{
  int counter = 1;

  foreach (var item in Model.Stuff) {
    ... some code ...
    counter = counter + 1;
  }
} 

回答5:

Not a direct answer to OP's problem, but it may help you too. You can declare a local variable next to some html inside a scope without trouble.

@foreach (var item in Model.Stuff)
{
    var file = item.MoreStuff.FirstOrDefault();

    <li><a href="@item.Source">@file.Name</a></li>
}

回答6:

to declare a var to be accessed across the page....top of the page usually works out. implicit or explicitly your choice.

          @{
               //implicit
               var something1 = "something";
               //explicit
               string something2 = "something";
          }


            @something1 //to display on the page
            @something2 //to display on the page

回答7:

you can put everything in a block and after easily write any code that you wish in that block just exactly the below code :

@{
        bool isUserConnected = string.IsNullOrEmpty(Model.CreatorFullName);
        if (isUserConnected)
        { // meaning that the viewing user has not been saved
            <div>
                <div> click to join us </div>
                <a id="login" href="javascript:void(0);" style="display: inline; ">join</a>
            </div>
        }
    }

it helps you to have at first a cleaner code and also you can prevent your page from loading many times different blocks of codes