Question

我正在尝试制作所有必需的文本字段，以确保用户不会将其留空。我试过这个，但由于某种原因，它没有用。我觉得我的逻辑是正确的，但这是一个快速逻辑的问题

这是我的代码：

let title = txtTitle.text!
let location = txtWhere.text!
let when = txtWhen.text!


    if title != nil && location != nil && when != nil {

        var titleArray = [String]()
        var whereArray = [String]()
        var whenArray = [String]()

        let titleObject = UserDefaults.standard.object(forKey: "saveTitle")
        let whereObject = UserDefaults.standard.object(forKey: "saveLocation")
        let whenObject = UserDefaults.standard.object(forKey: "saveWhen")




        if let tempTitle = titleObject as? [String] {

            titleArray = tempTitle
            titleArray.append(txtTitle.text!)
            print(titleArray)

        }
        else {

            titleArray = [txtTitle.text!]

        }

        if let tempWhere = whereObject as? [String] {

            whereArray = tempWhere
            whereArray.append(txtWhere.text!)
            //print(titleArray)

        }
        else {

            whereArray = [txtWhere.text!]

        }

        if let tempWhen = whenObject as? [String] {

            whenArray = tempWhen
            whenArray.append(txtWhen.text!)
            //print(titleArray)

        }
        else {

            whenArray = [txtWhen.text!]

        }


        UserDefaults.standard.set(titleArray, forKey: "saveTitle")
        UserDefaults.standard.set(whereArray, forKey: "saveLocation")
        UserDefaults.standard.set(whenArray, forKey: "saveWhen")
        txtTitle.text = ""
        txtWhere.text = ""
        txtWhen.text = ""
        txtTime.text = ""

    }
        else
    {

        errMsg.isHidden = false
        errMsg.text = "All fields are required"

    }
}

Answer 1

要可靠地检查文本字段的text属性是否不是nil而不是空的，请使用

if let title = txtTitle.text, !title.isEmpty,
   let location = txtWhere.text, !location.isEmpty,
   let when = txtWhen.text, !when.isEmpty { ...

如果所有条件都通过，则可以安全地解开三个变量。

Answer 2

一个。您不应强制解包（FILES.append("name.txt")）：而是检查可选值

湾您可能想要检查空字符串，而不仅仅是txtTitle.text!

那就是说，你可以测试这样的有效性：

nil

或者更好（谢谢Leo Dabus）：

let title = txtTitle.text
if title?.isEmpty == false {
    ...// title was filled
}

Answer 3

TEXTFIELD验证 ======================＆GT;

$cookiesRaw = $conn->httpRequest->getHeader('Cookie');

if(count($cookiesRaw)) {
    $cookiesArr = \GuzzleHttp\Psr7\parse_header($cookiesRaw)[0]; // Array of cookies
}

验证文本字段swift 3

3 个答案: