TextView 计数器键入和计数换行 Swift IOS

Posted 2023-02-24

【中文标题】TextView 计数器键入和计数换行 Swift IOS

【英文标题】：TextView Counter On Typing And Count New Line Swift IOS

【发布时间】：2018-04-10 17:13:23

【问题描述】：

我想在文本视图中计算换行符（“\n”）。

或者，更具体地说，我想让 textview 框在标签中键入 ( +1 ) 时对字符进行计数。当文本有新行并且计数器（标签）必须连续时，也计数（+2）。

这是我的代码：

func textView(_ textView: UITextView, shouldChangeTextIn range: NSRange, replacementText text: String) -> Bool 
    let allowedChars = 70
    let charsInTextView = -txtmessage.text.count
    let remainingChars = allowedChars + charsInTextView

    if (text == "\n") 
        let remainingChars = 70 - (txtmessage.text.count * 2 )

        countlabel.text = String(remainingChars)
    

    if (text != "\n")
        countlabel.text = String(remainingChars)
    

    return true

【参考方案1】：

import UIKit
import PlaygroundSupport
class ViewController: UIViewController 
    let textView = UITextView(frame: CGRect(origin: .zero, size: CGSize(width: 100, height: 100)))
    override func viewDidLoad() 
        super.viewDidLoad()
        view.addSubview(textView)
        textView.delegate = self
        textView.backgroundColor = .white
    


extension ViewController: UITextViewDelegate 
    func textViewDidChange(_ textView: UITextView) 
        guard let text = textView.text else  
            return
        
        let totalLength = text.count
        let newlineCount = text.filter $0 == "\n".count
        print("Total characters are \(totalLength) of which \(newlineCount) are newLines total of all characters counting newlines twice is \(totalLength + newlineCount)")
    

let v = ViewController()
v.preferredContentSize = CGSize(width: 1024, height: 768)
PlaygroundPage.current.liveView = v