我想实现的是，文本字段的格式应该是XXXX XXXX XXXX当用户点击show按钮时，它应该显示文本1234 5678 9123
请帮帮我
下面是我的代码，在那里我能够实现1234 5678 9123这种格式，屏蔽和存储原始数据是挂起的。
func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool
{
if textField.tag == 0 || textField.tag == 1 {
if string.isBackspace
{
if range.location == 5 || range.location == 10
{
textField.text?.removeLast()
}
}
if string == ""{
return true
}
//range.length will be greater than 0 if user is deleting text - allow it to replace
if range.length > 0
{
return true
}
//Don't allow empty strings
if string == " "
{
return false
}
//Check for max length including the spacers we added
if range.location > 13 //23
{
return false
}
var originalText = textField.text
let replacementText = string.replacingOccurrences(of: " ", with: "")
//Verify entered text is a numeric value
let digits = NSCharacterSet.decimalDigits
for char in replacementText.unicodeScalars
{
if !(digits as NSCharacterSet).longCharacterIsMember(char.value)
{
return false
}
}
//Put an empty space after every 4 places
if (originalText?.count)! > 0
{
if (originalText?.count)! < 5 && (originalText?.count)! % 4 == 0{
originalText?.append(" ")
}else if(((originalText?.count)! + 1) % 5 == 0){
originalText?.append(" ")
}
}
textField.text = originalText
}
//2 - Nick Name,3 - Recipient Name
if textField.tag == 2 || textField.tag == 3 {
//Max Limit for Nick Name and Benificiary Name is 65
if range.location > 64
{
return false
}
}
return true
}
如果我理解正确的话，您的要求是创建一个自定义的安全文本字段。要求是：
此外，它会很好，所有的文本字段功能将工作，包括复制粘贴，选择，插入代码在文本中间...
我创建了一个新项目，并很快以以下内容结束：
class ViewController: UIViewController {
@IBOutlet private var textField: UITextField?
private var actualText: String = ""
private var maskedText: String = ""
private var masked: Bool = true {
didSet {
refreshTextField()
}
}
@IBAction private func maskedTogglePressed(_ sender: Any) {
masked = !masked
}
private func refreshTextField() {
textField?.text = masked ? maskedText : actualText
}
}
extension ViewController: UITextFieldDelegate {
func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {
var newString = (actualText as NSString).replacingCharacters(in: range, with: string) // Apply new text
// Remove all whitespaces
newString = newString.replacingOccurrences(of: " ", with: "")
// Remove all that is not a number
newString = newString.filter("0123456789".contains)
// Split string into components of max 4
var components: [String] = {
var toDeplete = newString
var components: [String] = []
while !toDeplete.isEmpty {
let length = min(toDeplete.count, 4)
components.append(String(toDeplete.prefix(length)))
toDeplete.removeFirst(length)
}
return components
}()
// Limit to maximum of 3 components
if components.count > 3 {
components = Array(components[0..<3])
}
// Generate masked components, replacing all characters with X
let maskedComponents: [String] = components.map { String($0.map { character in return "X" }) }
// Add spaces
newString = components.joined(separator: " ")
let maskedText = maskedComponents.joined(separator: " ")
// Assign new strings
self.actualText = newString
self.maskedText = maskedText
// Refresh field
refreshTextField()
// Disallow text field to apply it's change
return false
}
}
在处理字符串时需要一些改进。但它起作用了。
代码被注释，并且应该提供关于解决方案的更多信息。
