目录
- 1、HTML标签转 富文本
- 2、计算富文本的Size
- 3、处理标签中包含 p 标签换行(独占一行)的问题
一、HTML标签转 富文本（这里写到String的扩展里面了）
extension String {
/// String 或者String HTML标签 转 html 富文本设置
/// - Parameters:
/// - font: 设置字体
/// - lineSpacing: 设置行高
/// - Returns: 默认不将 \n替换<br/> 返回处理好的富文本
func setHtmlAttributedString(font: UIFont? = UIFont.systemFont(ofSize: 16), lineSpacing: CGFloat? = 10) -> NSMutableAttributedString {
var htmlString: NSMutableAttributedString? = nil
do {
if let data = self.replacingOccurrences(of: "\n", with: "<br/>").data(using: .utf8) {
htmlString = try NSMutableAttributedString(data: data, options: [
NSAttributedString.DocumentReadingOptionKey.documentType: NSAttributedString.DocumentType.html,
NSAttributedString.DocumentReadingOptionKey.characterEncoding: NSNumber(value: String.Encoding.utf8.rawValue)], documentAttributes: nil)
let wrapHtmlString = NSMutableAttributedString(string: "\n")
// 判断尾部是否是换行符
if let weakHtmlString = htmlString, weakHtmlString.string.hasSuffix("\n") {
htmlString?.deleteCharacters(in: NSRange(location: weakHtmlString.length - wrapHtmlString.length, length: wrapHtmlString.length))
}
}
} catch {
}
// 设置富文本字的大小
if let font = font {
htmlString?.addAttributes([
NSAttributedString.Key.font: font], range: NSRange(location: 0, length: htmlString?.length ?? 0))
}
// 设置行间距
if let weakLineSpacing = lineSpacing {
let paragraphStyle = NSMutableParagraphStyle()
paragraphStyle.lineSpacing = weakLineSpacing
htmlString?.addAttribute(.paragraphStyle, value: paragraphStyle, range: NSRange(location: 0, length: htmlString?.length ?? 0))
}
return htmlString ?? NSMutableAttributedString(string: self)
}
}
二、计算富文本的Size
let strHtml = "<p style='color:green'>首付<span style='color:#e83c36;'>5000元</span>，提前付<span style='color:red'>3倍月供</span>，月供<span style='color:red'>3000元</span>(48期)</p>"
let attributedText = strHtml.setHtmlAttributedString(font: UIFont.systemFont(ofSize: 20), lineSpacing: 10)
let textSize = attributedText.boundingRect(with: CGSize(width: kScreenW - 40, height: CGFloat.greatestFiniteMagnitude), options: [.usesLineFragmentOrigin, .usesFontLeading], context: nil).size
三、处理标签中包含 p 标签换行(独占一行)的问题
-
3.1、问题描述：如果p标签是最大的标签，生成的富文本会自动换行，展示的时候多一行的高度，如下
p标签造成的问题 -
3.2、目前的处理办法：判断生成的富文本字符串
结尾里面是否有\n，如果有我们就删除掉，代码如下，htmlString是HTML标签转化后的富文本let wrapHtmlString = NSMutableAttributedString(string: "\n") // 判断尾部是否是换行符 if let weakHtmlString = htmlString, weakHtmlString.string.hasSuffix("\n") { htmlString?.deleteCharacters(in: NSRange(location: weakHtmlString.length - wrapHtmlString.length, length: wrapHtmlString.length)) }处理后的效果图如下
处理后的效果图
具体的 测试用例 在 StringExtensionViewController.swift 的 test119() 方法里面
