# Response.Redirect: true or false?

When you use `Response.Redirect` with its second parameter set to `true`, it triggers a call to `Response.End()`

```csharp
Response.Redirect("Login.aspx");              // default is true
Response.Redirect("Login.aspx", true);        // same as above
```

This causes [ASP.NET](http://ASP.NET) to throw a `ThreadAbortException`, which is not ideal from a performance or diagnostics standpoint.

### So, What Should We Do?

The recommended approach is to use `false` it as the second parameter. This allows the redirection to occur without forcibly terminating the current request:

```csharp
Response.Redirect("Login.aspx", false);
HttpContext.Current.ApplicationInstance.CompleteRequest();
return;
```

Calling `CompleteRequest()` ensures that the request finishes gracefully — a "soft" redirect, if you will.

### But There's a Catch in Web Forms

When using `Response.Redirect(..., false)` in [ASP.NET](http://ASP.NET) Web Forms, you may encounter issues with certain page-level components like `LinqDataSource`.

These components continue executing their logic even after the redirect is issued. If a required parameter (e.g., `UserId`) isn’t provided in time, you'll get a type mismatch error — typically because these controls bind data early in the page lifecycle.

**Common error:**

```csharp
[ParseException: Operator '==' incompatible with operand types 'Guid' and 'Object']
```

To avoid this error, if you're setting `WhereParameters` in `Page_Load`You **must** use `Response.Redirect(..., true)` to immediately terminate the pipeline before any control processing begins.

### Want to Use `false` and Still Avoid Errors?

If you’d like to avoid `ThreadAbortException` **and** safely use controls like `LinqDataSource`, the best practice is to perform your redirect check inside the `Page_Init` method.

Why? Because `Page_Init` occurs very early in the page lifecycle — before data binding or parameter evaluation. So redirecting here will safely exit the page before `LinqDataSource` or similar controls need their parameters.

Here’s how it looks:

```csharp
protected void Page_Init(object sender, EventArgs e)
{
    if (Request.Cookies["isAuthenticated"] == null)
    {
        Response.Redirect("Login.aspx", false);
        HttpContext.Current.ApplicationInstance.CompleteRequest();
        return;
    }
}

protected void Page_Load(object sender, EventArgs e)
{
    if (!IsPostBack)
    {
        LinqDataSource1.WhereParameters["UserId"].DefaultValue = GetUserId().ToString();
    }
}
```

### Final Thoughts

Using `false` with `CompleteRequest()` is a cleaner, more graceful way to redirect in [ASP.NET](http://ASP.NET) Web Forms — **but only if you're careful with the page lifecycle.**  
Move your redirect checks to `Page_Init` whenever you’re working with components that bind data early, you’ll avoid exceptions and headaches.