How to fix an operator to a void call in a button?

Question

I'm a beginner C# dev and I am forgetting something. The (!ValidateCleared(actionsChecked))code is throwing and error the Operator ! cannot be applied to a void. Not sure how to fix this in this example. I tried keeping it a bool and using a break, but the actions didn't behave as expected. It only checked the one action.

protected void btnSubmit_Click(object sender, EventArgs e)
{
    ValidateActionSelected();enter code here
    ValidateCleared(actionsChecked);

    if (!ValidateCleared(actionsChecked))
    {
        if (String.Equals(ddlActionsAndDocuments.SelectedItem.Text.ToString(), "XXX YYY") || String.Equals(ddlActionsAndDocuments.SelectedItem.Text.ToString(), "XXX ZZZ"))
        {
            reqEffectiveDate.ErrorMessage = "";
        }

        if (ddlActionsAndDocuments.SelectedValue == ActionTypes.XXXYYY ||
            ddlActionsAndDocuments.SelectedValue == ActionTypes.XXXYYYDenial ||
            ddlActionsAndDocuments.SelectedValue == ActionTypes.XXXzzz)
        {
            ValidateXXXYYY(actionsChecked, ddlActionsAndDocuments.Text);
        }

        if (ddlActionsAndDocuments.SelectedValue == InsuranceActionTypes.WWW ||
            ddlActionsAndDocuments.SelectedValue == InsuranceActionTypes.YYYZZZ ||
            ddlActionsAndDocuments.SelectedValue == InsuranceActionTypes.YYYWWW ||
            ddlActionsAndDocuments.SelectedValue == InsuranceActionTypes.YYYWaived)
        {
            ValidateCertificate(actionsChecked, ddlActionsAndDocuments.Text);
        }
    }
}

private void ValidateCleared(List<xxCaseEntity> actionsChecked)
{

    //bool error = false;

    foreach (xxCaseEntity ACTIONyy in actionsChecked)
    {
        if (ACTIONyy.XXStatusCode == 40 || ACTIONyy.XXStatusCode == 45)
        {
            //error = true;
            DisplayErrorMessage("FR Action Cannot Apply to " + ACTIONyy.CaseIdentifier);

            actionsChecked.Remove(ACTIONyy);
            //break;
        }

    }
    return;

    //return error;
}

If you want to use `ValidateCleared()` as if it returns `bool` rather than `void`, try making it actually return `bool` rather than `void`. Change the declared return type, and alter the code in `ValidateCleared()` so it returns true or false in every path through the method. — 15ee8f99-57ff-4f92-890c-b56153, Sep 26 '17 at 19:05
the bool method works fine. But for other functionality I need it to return void. — Teresa Scudder, Sep 26 '17 at 19:07
@TeresaScudder No, you don't ever need it to return void. You can just ignore the return value. — 15ee8f99-57ff-4f92-890c-b56153, Sep 26 '17 at 19:08
Explain in detail what you mean. If a method returns a value, you can use the value or ignore the value. What do you think "return" means? — 15ee8f99-57ff-4f92-890c-b56153, Sep 26 '17 at 19:13
It may or may not return a value. what I am doing is checking if certain actions meet my criteria. if yes, then do nothing and the error msg is displayed. if it doesn't then remove the action and send valid ones to my webapi. That is what I am trying to do. — Teresa Scudder, Sep 26 '17 at 19:18
If you want `ValidateCleared()` to return `bool`, make it return `bool`. — 15ee8f99-57ff-4f92-890c-b56153, Sep 26 '17 at 19:20

Wizengamot · Answer 1 · 2017-09-27T21:28:06.840

The fixed code is below

protected void btnSubmit_Click(object sender, EventArgs e)
    {
        ValidateActionSelected();enter code here
        ValidateCleared(actionsChecked);

        if (!ValidateCleared(actionsChecked))
        {
            if (String.Equals(ddlActionsAndDocuments.SelectedItem.Text.ToString(), "XXX YYY") || String.Equals(ddlActionsAndDocuments.SelectedItem.Text.ToString(), "XXX ZZZ"))
            {
                reqEffectiveDate.ErrorMessage = "";
            }

            if (ddlActionsAndDocuments.SelectedValue == ActionTypes.XXXYYY ||
                ddlActionsAndDocuments.SelectedValue == ActionTypes.XXXYYYDenial ||
                ddlActionsAndDocuments.SelectedValue == ActionTypes.XXXzzz)
            {
                ValidateXXXYYY(actionsChecked, ddlActionsAndDocuments.Text);
            }

            if (ddlActionsAndDocuments.SelectedValue == InsuranceActionTypes.WWW ||
                ddlActionsAndDocuments.SelectedValue == InsuranceActionTypes.YYYZZZ ||
                ddlActionsAndDocuments.SelectedValue == InsuranceActionTypes.YYYWWW ||
                ddlActionsAndDocuments.SelectedValue == InsuranceActionTypes.YYYWaived)
            {
                ValidateCertificate(actionsChecked, ddlActionsAndDocuments.Text);
            }
        }
    }

    private bool ValidateCleared(List<xxCaseEntity> actionsChecked)
    {
        List<xxCaseEntity> removeItems = new List<xxCaseEntity>();
        foreach (xxCaseEntity ACTIONyy in actionsChecked)
        {
            if (ACTIONyy.XXStatusCode == 40 || ACTIONyy.XXStatusCode == 45)
            {
                DisplayErrorMessage("FR Action Cannot Apply to " + ACTIONyy.CaseIdentifier);

                //actionsChecked.Remove(ACTIONyy);
                removeItems.Add(ACTIONyy);
            }
        }
        foreach(xxCaseEntity ACTIONyy in removeItems)
        {
            actionsChecked.Remove(ACTIONyy);
        }
        return true;
    }

Your version won't compile. – 15ee8f99-57ff-4f92-890c-b56153 Sep 26 '17 at 19:09 — 15ee8f99-57ff-4f92-890c-b56153, Sep 26 '17 at 19:09

How to fix an operator to a void call in a button?

1 Answers1