function isURL(_url)
{
    let result = false;
    let w = window;

    if (!w._check_input)
    {
        let input = document.createElement("input");
        input.type      = "url";
        input.required  = true;

        w._check_input = input;
    }

    w._check_input.value = _url;
    if (w._check_input.checkValidity()) result = true;

    return result;
}

您可以使用ajax请求来检查字符串是否有效的url和可访问的

(function() { $("input").change(function() { const check = $.ajax({ url : this.value, dataType: "jsonp" }); check.then(function() { console.log("Site is valid and registered"); }); //expected output check.catch(function(reason) { if(reason.status === 200) { return console.log("Site is valid and registered"); } console.log("Not a valid site"); }) }); })() <script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script> <input type="text" placeholder="Please input url to check ? ">

和我一起工作

function isURL(str) {
  var regex = /(http|https):\/\/(\w+:{0,1}\w*)?(\S+)(:[0-9]+)?(\/|\/([\w#!:.?+=&%!\-\/]))?/;
  var pattern = new RegExp(regex); 
return pattern.test(str);
}

你可以使用URL原生API:

  const isUrl = string => {
      try { return Boolean(new URL(string)); }
      catch(e){ return false; }
  }

我不能评论最接近#5717133的帖子，但下面是我想出如何让@tom-gullen正则表达式工作的方法。

/^(https?:\/\/)?((([a-z\d]([a-z\d-]*[a-z\d])*)\.)+[a-z]{2,}|((\d{1,3}\.){3}\d{1,3}))(\:\d+)?(\/[-a-z\d%_.~+]*)*(\?[;&a-z\d%_.~+=-]*)?(\#[-a-z\d_]*)?$/i

function isURL(_url)
{
    let result = false;
    let w = window;

    if (!w._check_input)
    {
        let input = document.createElement("input");
        input.type      = "url";
        input.required  = true;

        w._check_input = input;
    }

    w._check_input.value = _url;
    if (w._check_input.checkValidity()) result = true;

    return result;
}