IOS UITextField 事件列表

//UITextFieldDelegate
 import UIKit
 class ViewController：UIViewController,UITextFieldDelegate {
 override func viewDidLoad() {
 super.viewDidLoad()
 // Do any additional setup after loading the view,typically from a nib.
 let rect = CGRect(x：10, y：80, width：300, height：
 )
 let textField = UITextField(frame：rect)
 textField.placeholder = “Bank card no”
 textField.autocorrectionType =UITextAutocorrectionType.no
 textField.returnKeyType = UIReturnKeyType.done
 textField.clearButtonMode =UITextFieldViewMode.whileEditing
 textField.keyboardType = UIKeyboardType.numberPad
 textField.keyboardAppearance =
 UIKeyboardAppearance.dark
 textField.delegate = self
 textField.borderStyle = UITextBorderStyle.line
 }
 override func didReceiveMemoryWarning() {
 super.didReceiveMemoryWarning()
 // Dispose of any resources that can be recreated.
 }
 func textFieldShouldBeginEditing(_ textField：UITextField) -> Bool
 // return NO to disallow editing.
 {
 return true
 }
 func textFieldDidBeginEditing(_ textField：UITextField)
 // became first responder
 {
 }
 func textFieldShouldEndEditing(_ textField：UITextField) -> Bool
 // return YES to allow editing to stopand to resign first responder status．NO to disallow the editing session to end
 {
 return true
 }
 func textFieldDidEndEditing(_ textField：UITextField)
 // may be called if forced even if shouldEndEditing returnsNO (e.g．view removed from window) or endEditing：YES called
 {
 }
 func textField(_ textField：UITextField,shouldChangeCharactersIn range：NSRange,replacementString string：String) -> Bool {
 // return NO to not change text
 return true
 }
 func textFieldShouldClear(_ textField：UITextField) -> Bool {
 return true
 }
 func textFieldShouldReturn(_ textField：UITextField)-> Bool {
 return true
 }
 }
//方法包括：
 将要开始编辑状态时调用此协议方法。
 编辑状态开始后调用此协议方法。
 编辑状态将要结束后调用此协议方法。
 编辑状态结束后调用此协议方法。
 协议方法在文本将要输入的时候调用。
 协议方法返回一个BOOL值，指明是否允许根据用户请求清除内容。
 协议方法返回一个BOOL值，指明是否允许在按下Enter键时结束编辑。