如何解决类型错误：在Laravel中运行的参数太少

I am creating a web site. In this web site, I have created a registration form. So , I have created a function called saveInvoice to insert all the data into the database. After that I created another function called sendemail. I have passed 2 arguments to sendmail function from saveInvoice like this -

$this->sendemail($request, $total); 

But , when I click Submit button, it gives me this error -

Symfony \ Component \ Debug \ Exception \ FatalThrowableError (E_RECOVERABLE_ERROR)
Type error: Too few arguments to function App\Http\Controllers\InvoicesController::sendemail(), 1 passed and exactly 2 expected

How can I Fix this ??

Here is saveInvoice function.

public function saveInvoice(Request $request)
    {
        if (Auth::user()) {
            $settings = Setting::find(1);
            $invoiceNo = $settings->invoiceprefix . '' . str_pad($settings->invoiceno, $settings->invoicepadding, 0, STR_PAD_LEFT);

            $Qty = $request->input('Qty');
            $price = $request->input('price');
            $total = $Qty * $price;

            $invoice = new Invoice();
            $invoice->invoicereference = $invoiceNo;
            $invoice->firstname = $request->fname;

            $invoice->save();

            if ($invoice == null) {
                return redirect()->back()->with('msg', 'invalid request');
            } else {
                $this->sendemail($request, $total);
                return redirect()->route('invoice.preview', $invoiceNo);
            }
        }

    }

Here is sendemail function.

public function sendemail(Request $request, $total)
    {
        $invoiceNo = $request->input('invoiceNo');
        $fname = $request->input('fname');
        $sendemail = $request->input('email');

        $data = [];
        $data['invoiceNo'] = $invoiceNo;
        $data['fname'] = $fname;
        $data['total'] = $total;
        $data['sendemail'] = $sendemail;

        Mail::send(['html' => 'mail'], $data, function ($message) use ($data) {
            $message->to($data["sendemail"], 'TicketBooker')->subject
            ('CheapEfares Order Invoice');
            $message->from('kistlakall@gmail.com', 'CheapEfares');
        });
        return Redirect::back();
    }

Routes.

Route::Post('invoice/addinvoice', [
    'uses' => 'InvoicesController@saveInvoice',
    'as' => 'invoice.save'
]);

Route::get('sendemail','InvoicesController@sendemail')->name('sendemail');

As you are calling function sendemail() from route. It's passing only one parameter to it like:

sendemail($request);

Also $total variable not being used in function sendemail() at all. So remove it or make it optional like:

public function sendemail(Request $request, $total = "") {
    $invoiceNo = $request->input('invoiceNo');
    $fname = $request->input('fname');
    $sendemail = $request->input('email');

    $data = [];
    $data['invoiceNo'] = $invoiceNo;
    $data['fname'] = $fname;
    $data['total'] = empty($total) ? 0 : $total;
    $data['sendemail'] = $sendemail;

    Mail::send(['html' => 'mail'], $data, function ($message) use ($data) {
        $message->to($data["sendemail"], 'TicketBooker')->subject
                ('CheapEfares Order Invoice');
        $message->from('kistlakall@gmail.com', 'CheapEfares');
    });
    return Redirect::back();
}

Also you can pass total variable through routes as well.

Route::get('sendemail/{total}','InvoicesController@sendemail')->name('sendemail');

Do not use Request in the sendemail() function definition, as you are already passing $request and $total into it. Request $request will try to instantiate a new Request Object and will look for it, whereas you are already passing a simple variable. Use it like this

public function sendemail($request, $total){ .. .. }

Put a default value, so it will not be necessary to pass the argument to the function

public function sendemail(Request $request = null, $total = '') {}