fastadmin的编辑器只有一个是可以远程下载图片的，但功能用起来并不习惯，所以经过修改增加对ueditor编辑器对远程图片下载的功能。分享给大家

在application/admin/controller/cms/Ajax.php增加

use GuzzleHttp\Client;
use Symfony\Component\HttpFoundation\StreamedResponse;
/**
* 下载图片
*/
public function download()
{
    $url = $this->request->request("url");
    $contentType = '';
    try {
        $client = new Client();
        $response = $client->request('GET', $url, ['stream' => true, 'verify' => false, 'allow_redirects' => ['strict' => true]]);        
        $body = $response->getBody();
        $contentType = $response->getHeader('Content-Type');
        $contentType = $contentType[0] ?? 'image/png';
    } catch (\Exception $e) {
        $this->error("图片下载失败");
    }

    $contentTypeArr = explode('/', $contentType);
    if ($contentTypeArr[0] !== 'image') {
        $this->error("只支持图片文件");
    }

    $response = new StreamedResponse(function () use ($body) {
        while (!$body->eof()) {
            echo $body->read(1024);
        }
    });
    $response->headers->set('Content-Type', $contentType);
    $response->send();
    return;
}

在public/assets/js/backend/cms/archives.js的

api: {
   ...
   bindevent: function () {
      ...
      var getImageFromUrl = function (url, callback) {
                    var req = new XMLHttpRequest();
                    req.open("GET", Fast.api.fixurl("cms/ajax/download") + "?url=" + encodeURIComponent(url), true);
                    req.responseType = "blob";
                    req.onload = function (event) {
                        var file;
                        if (req.status >= 200 && req.status < 300 || req.status == 304) {
                            var blob = req.response;
                            var mimetype = blob.type || "image/png";
                            var mimetypeArr = mimetype.split("/");
                            if (mimetypeArr[0].toLowerCase() === 'image') {
                                var suffix = ['jpeg', 'jpg', 'bmp', 'gif', 'png', 'webp', 'svg+xml'].indexOf(mimetypeArr[1]) > -1 ? mimetypeArr[1] : 'png';
                                suffix = suffix == 'svg+xml' ? 'svg' : suffix;
                                var filename = Math.random().toString(36).substring(5, 15) + "." + suffix;
                                file = new File([blob], filename, {type: mimetype});
                            }
                        }
                        callback.call(this, file);
                    };
                    req.send();
                    return;
                };
                //远程图片下载
                $(document).on("click", ".btn-localimg", function (a) {
                    var Upload = require('upload');
                    var that = $("#c-content").val();
                    var content = $("#c-content").val();
                    var staging = {}, orgined = {}, index = 0, images = 0, completed = 0, failured = 0;
                    // debugger
                    var checkrestore = function () {
                        
                        if (completed + failured >= images) {
                            $.each(staging, function (i, j) {
                                UE.getEditor("c-content").setContent(that.replace("<code>" + i + "</code>", j));
                            });
                            Toastr.info("成功：" + completed + " 失败：" + failured);
                        }
                        // debugger
                    };
                    content.replace(/<code>([\s\S]*?)<\/code>/g, function (code) {
                            staging[index] = code;
                            return "<code>" + index + "</code>";
                            // debugger
                        }
                    );

                    content = content.replace(/<img([\s\S]*?)\ssrc\s*=\s*('|")((http(s?):)([\s\S]*?))('|")([\s\S]*?)[\/]?>/g, function () {
                        images++;
                        var url = arguments[3];
                        var placeholder = '<img src="' + Config.site.cdnurl + "/assets/img/loading.gif" + '" data-index="' + index + '" />';
                        //如果是云存储的链接或本地的链接,则忽略
                        if ((Config.upload.cdnurl && url.indexOf(Config.upload.cdnurl) > -1) || url.indexOf(location.origin) > -1) {
                            completed++;
                            return arguments[0];
                        } else {
                            orgined[index] = arguments[0];
                        }

                        var attributes = arguments[1] + " " + arguments[8];
                        attributes = attributes.replace(/'/g, '"');
                        // debugger
                        //下载远程图片
                        (function (index, url, placeholder, attributes) {
                            getImageFromUrl(url, function (file) {
                                if (!file) {
                                    failured++;
                                    content = content.replace(placeholder, orgined[index]);
                                    UE.getEditor("c-content").setContent(content);
                                    checkrestore();
                                } else {
                                    Upload.api.send(file, function (data) {
                                        completed++;
                                        content = content.replace(placeholder, '<img src="' + Fast.api.cdnurl(data.url, true) + '" ' + attributes + ' />');
                                        UE.getEditor("c-content").setContent(content);
                                        checkrestore();
                                        // debugger
                                    }, function (data) {
                                        failured++;
                                        content = content.replace(placeholder, orgined[index]);
                                        UE.getEditor("c-content").setContent(content);
                                        checkrestore();
                                    });
                                }
                            });
                        })(index, url, placeholder, attributes);
                        index++;
                        return placeholder;
                        // debugger
                    });
                    if (index > 0) {
                        UE.getEditor("c-content").setContent(content);
                        // debugger
                    } else {
                        Toastr.info("没有需要下载的远程图片");
                    }
                });
   }
}

//在view中增加按钮 
<a href="javascript:" class="btn btn-xs btn-info btn-localimg" data-toggle="tooltip" data-title="远程下载图片"><i class="fa fa-camera"></i> {:__('远程下载图片')}</a> 即可实现远程图片下载功能 当然其他编辑器也可以实现 修改内容写入方法即可