在JavaScript中是否有一种方法来检查字符串是否是URL?

regex被排除在外,因为URL很可能写成stackoverflow;也就是说,它可能没有。com, WWW或http。


当前回答

我将函数更改为Match +,在这里用斜杠和它的工作:(http://和https)进行更改

function isValidUrl(userInput) {
    var res = userInput.match(/(http(s)?:\/\/.)?(www\.)?[-a-zA-Z0-9@:%._\+~#=]{2,256}\.[a-z]{2,6}\b([-a-zA-Z0-9@:%_\+.~#?&//=]*)/g);
    if(res == null)
       return false;
    else
       return true;
}

其他回答

我使用下面的函数来验证URL是否有http/https:

function isValidURL(string) { var res = string.match(/(http(s)?:\/\/.)?(www\.)?[-a-zA-Z0-9@:%._\+~#=]{2,256}\.[a-z]{2,6}\b([-a-zA-Z0-9@:%_\+.~#?&//=]*)/g); return (res !== null) }; var testCase1 = "http://en.wikipedia.org/wiki/Procter_&_Gamble"; console.log(isValidURL(testCase1)); // return true var testCase2 = "http://www.google.com/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&docid=nIv5rk2GyP3hXM&tbnid=isiOkMe3nCtexM:&ved=0CAUQjRw&url=http%3A%2F%2Fanimalcrossing.wikia.com%2Fwiki%2FLion&ei=ygZXU_2fGKbMsQTf4YLgAQ&bvm=bv.65177938,d.aWc&psig=AFQjCNEpBfKnal9kU7Zu4n7RnEt2nerN4g&ust=1398298682009707"; console.log(isValidURL(testCase2)); // return true var testCase3 = "https://sdfasd"; console.log(isValidURL(testCase3)); // return false var testCase4 = "dfdsfdsfdfdsfsdfs"; console.log(isValidURL(testCase4)); // return false var testCase5 = "magnet:?xt=urn:btih:123"; console.log(isValidURL(testCase5)); // return false var testCase6 = "https://stackoverflow.com/"; console.log(isValidURL(testCase6)); // return true var testCase7 = "https://w"; console.log(isValidURL(testCase7)); // return false var testCase8 = "https://sdfasdp.ppppppppppp"; console.log(isValidURL(testCase8)); // return false

你可以使用URL原生API:

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

一个有答案的相关问题

或者来自Devshed的Regexp:

function validURL(str) {
  var pattern = new RegExp('^(https?:\\/\\/)?'+ // protocol
    '((([a-z\\d]([a-z\\d-]*[a-z\\d])*)\\.)+[a-z]{2,}|'+ // domain name
    '((\\d{1,3}\\.){3}\\d{1,3}))'+ // OR ip (v4) address
    '(\\:\\d+)?(\\/[-a-z\\d%_.~+]*)*'+ // port and path
    '(\\?[;&a-z\\d%_.~+=-]*)?'+ // query string
    '(\\#[-a-z\\d_]*)?$','i'); // fragment locator
  return !!pattern.test(str);
}
function isURL(str) {
  var pattern = new RegExp('^(https?:\\/\\/)?'+ // protocol
  '((([a-z\\d]([a-z\\d-]*[a-z\\d])*)\\.?)+[a-z]{2,}|'+ // domain name
  '((\\d{1,3}\\.){3}\\d{1,3}))'+ // OR ip (v4) address
  '(\\:\\d+)?(\\/[-a-z\\d%_.~+]*)*'+ // port and path
  '(\\?[;&a-z\\d%_.~+=-]*)?'+ // query string
  '(\\#[-a-z\\d_]*)?$','i'); // fragment locator
  return pattern.test(str);
}

另一种方法是使用Node.JS的DNS模块。

DNS模块提供了一种执行名称解析的方法,使用它可以验证url是否有效。

const dns = require('dns');
const url = require('url'); 

const lookupUrl = "https://stackoverflow.com";
const parsedLookupUrl = url.parse(lookupUrl);

dns.lookup(parsedLookupUrl.protocol ? parsedLookupUrl.host 
           : parsedLookupUrl.path, (error,address,family)=>{

              console.log(error || !address ? lookupUrl + ' is an invalid url!' 
                           : lookupUrl + ' is a valid url: ' + ' at ' + address);
    
              }
);

这样您就可以检查url是否有效以及是否存在