Swift：为浏览器创建搜索栏

Question

使用快速获取错误（在源文件中使用编辑器占位符来创建网络浏览器，如果用户添加http或仅添加www或仅添加单词以在google.com中开始搜索，则搜索栏应该能够获取。

 func searchBarSearchButtonClicked(_ searchBar: UISearchBar) {

     let urlString = mySearchBar.text

if urlString?.starts(with: "http://") ?? <#default value#> || ((urlString?.starts(with: "https://")) != nil){
    loadUrl(urlString!)
} else if (urlString?.contains("www"))!{
    loadUrl("http://\(urlString!)")
}else {
    searchTextOnGoogle(urlString!)

}
}


func loadUrl(_ urlString: String) {
    guard let url = URL(string: urlString) else { return }

    let urlRequest = URLRequest(url: url)
    myWebView.loadRequest(urlRequest)
}

func searchTextOnGoogle(_ text: String) {
    let textComponents = text.components(separatedBy: " ")

    let searchString = textComponents.joined(separator: "+")

    guard let url = URL(string: "https://www.google.com/search?q=" + searchString) else { return }

    let urlRequest = URLRequest(url: url)
    myWebView.loadRequest(urlRequest)
}

Answer 1

由于错误提示，您错过了代码中的占位符。<#default value#>