Question: I am using C# with ASP.NET.

How do I check if a parameter has been received as a POST variable?

I need to do different actions if the parameter has been sent via POST or via GET.

Answer: 
Use this for GET values:

```
Request.QueryString["key"]

```

And this for POST values

```
Request.Form["key"]

```

Also, this will work if you don't care whether it comes from GET or POST, or the [HttpContext.Items](http://msdn.microsoft.com/en-us/library/system.web.httpcontext.items.aspx) collection:

```
Request["key"]

```

Another thing to note (if you need it) is you can check the type of request by using:

```
Request.RequestType

```

Which will be the verb used to access the page (usually GET or POST). `Request.IsPostBack` will usually work to check this, but only if the POST request includes the hidden fields added to the page by the ASP.NET framework.
Use the 

> 
> Request.Form[]
> 
> 
> 

for POST variables, 

> 
> Request.QueryString[]
> 
> 
> 

for GET.