How can we declare a local variable and infer its value?

Question

I declared such a variable

@{ int i = 1; } 

Now, inside the foreach I want to assign a value to me every time the loop is processed;

  @foreach (var line in Model.Cart.Lines) { <input type="hidden" name=" item_name_@i " value="@line.Product.ProductName" /> <input type="hidden" name=" amount_@i " value="@line.Product.Price" /> <input type="hidden" name=" quantity_@i " value="@line.Quantity" /> @i++; } 

but it does not work.

Any solution?

Answer 1

If you need access to the index, it makes sense to use the usual for loop:

 @for (int i = 0; i < Model.Cart.Lines.Count; i++) { var line = Model.Cart.Lines[i]; ... } 

Alternatively, you can use the LINQ expression:

 @foreach (var item in Model.Cart.Lines.Select((x, i) => new { Line = x, Index = i })) { // Now you can access, for example, `item.Line` for the line, and // `item.Index` for the index (ie `i`) ... } 

Answer 2

You have not explained what does not work, but from your code it seems that the value of the variable “i” is not increasing, instead you check the output of “0 ++;”.

This is because the purpose of the @ symbol in a razor

• for conclusion
• and therefore it displays the identifier "i", and then continues the remaining text "++;".

In order to achieve what you apparently want to do (just increase the value of i), you must wrap it in a code block as follows:

 @{ i++; } 

However, if you want to display the value of i before increasing it, you must wrap it in an expression block, as shown below:

 @(i++) 

Answer 3

I think about the area. see http://msdn.microsoft.com/en-us/vs2010trainingcourse_aspnetmvc3razor.aspx

try one block of code, for example:

 @{ var i = 1; var tmp = ""; foreach (var line in Model.Cart.Lines) { tmp = "item_name_" + i; <input type="hidden" name="@tmp" value="@line.Product.ProductName" /> i++; } }