适用场景：

• 你是前端开发人员，要开发一个小模块，需要用到线上的环境（账号、数据、跨域等），但你又没有权限往线上传文件
• 你是移动测试人员，需要将一组接口的返回结果替换为另一组，最简单的办法就是使用Fiddler修改接口返回结果

实现脚本代码：

import System;import System.Windows.Forms;import Fiddler;import System.IO;// INTRODUCTION// This is the FiddlerScript Rules file, which creates some of the menu commands and// other features of Fiddler. You can edit this file to modify or add new commands.//// The original version of this file is named SampleRules.js and it is in the// \Program Files\Fiddler\ folder. When Fiddler first starts, it creates a copy named// CustomRules.js inside your \Documents\Fiddler2\Scripts folder. If you make a // mistake in editing this file, simply delete the CustomRules.js file and restart// Fiddler. A fresh copy of the default rules will be created from the original// sample rules file.// GLOBALIZATION NOTE:// Be sure to save this file with UTF-8 Encoding if using any non-ASCII characters// in strings, etc.// JScript.NET Reference// http://fiddler2.com/r/?msdnjsnet//// FiddlerScript Reference// http://fiddler2.com/r/?fiddlerscriptcookbook//// FiddlerScript Editor: // http://fiddler2.com/fiddlerscript-editor/** * Fiddler 自定义脚本 *  * @author frank * @email frank@mondol.info * @created 2016-08-22 */class Handlers{    /******************** 配置开始 ********************/    /* 客户端IP白名单 */    static var sClientIpWhitelist = ["127.0.0.1","192.168.11.29","192.168.11.89"];            /*      * 请求URL黑名单     * 此名单采用模糊匹配，只要请求URL包含此名单中的字符串就满足条件     */    static var sUrlBacklist = ["/generate_204"];                       /******************** 配置结束 ********************/    /******************** 回调开始 ********************/    /**     * 开始请求前的回调     *      * @return {boolean} true: 终止后面的操作 | false: 不终止     */    static function OnBeforeRequestCallback(oSession: Session) {        //劫持指定路径下的所有请求        var hUrl = "www.shouxiner.com/MyHome/";        if(oSession.HTTPMethodIs("GET") && oSession.uriContains(hUrl)){            var filePath = MapUrlToFilePath(oSession.url, hUrl, "D:\\MyWeb");            if(File.Exists(filePath)) {                oSession.LoadResponseFromFile(filePath);                return true;            }        }    }    /**     * PEEK响应头的回调     *      * @return {boolean} true: 终止后面的操作 | false: 不终止     */    static function OnPeekAtResponseHeadersCallback(oSession: Session) {    }    /**     * 返回响应头前的回调     *      * @return {boolean} true: 终止后面的操作 | false: 不终止     */    static function OnBeforeResponseCallback(oSession: Session) {    }    /******************** 回调结束 ********************/                            /******************** 列配置开始 ********************/    // The following snippet demonstrates a custom-bound column for the Web Sessions list.    // See http://fiddler2.com/r/?fiddlercolumns for more info    public static BindUIColumn("Method", 60)    function FillMethodColumn(oS: Session): String {        return oS.RequestMethod;    }        public static BindUIColumn("ClientIP", 120)    function FillClientIPColumn(oS: Session): String {        return oS.clientIP;    }       /******************** 列配置结束 ********************/    // The following snippet demonstrates how to create a custom tab that shows simple text    /*    public BindUITab("Flags")    static function FlagsReport(arrSess: Session[]):String {    var oSB: System.Text.StringBuilder = new System.Text.StringBuilder();    for (var i:int = 0; i
     请检查并关闭你的WiFi代理...
 By Frank",null);                oSession.Ignore();            }        }                        /** 隐藏所有来源请求 **/        if(m_HideAllRequest){            oSession.Ignore();         }                        // Sample Rule: Color ASPX requests in RED        // if (oSession.uriContains(".aspx")) {    oSession["ui-color"] = "red";    }        // Sample Rule: Flag POSTs to fiddler2.com in italics        // if (oSession.HostnameIs("www.fiddler2.com") && oSession.HTTPMethodIs("POST")) {    oSession["ui-italic"] = "yup";    }        // Sample Rule: Break requests for URLs containing "/sandbox/"        // if (oSession.uriContains("/sandbox/")) {
            //     oSession.oFlags["x-breakrequest"] = "yup";    // Existence of the x-breakrequest flag creates a breakpoint; the "yup" value is unimportant.        // }        if ((null != gs_ReplaceToken) && (oSession.url.indexOf(gs_ReplaceToken)>-1)) {   // Case sensitive            oSession.url = oSession.url.Replace(gs_ReplaceToken, gs_ReplaceTokenWith);         }        if ((null != gs_OverridenHost) && (oSession.host.toLowerCase() == gs_OverridenHost)) {            oSession["x-overridehost"] = gs_OverrideHostWith;         }        if ((null!=bpRequestURI) && oSession.uriContains(bpRequestURI)) {            oSession["x-breakrequest"]="uri";        }        if ((null!=bpMethod) && (oSession.HTTPMethodIs(bpMethod))) {            oSession["x-breakrequest"]="method";        }        if ((null!=uiBoldURI) && oSession.uriContains(uiBoldURI)) {            oSession["ui-bold"]="QuickExec";        }        if (m_SimulateModem) {            // Delay sends by 300ms per KB uploaded.            oSession["request-trickle-delay"] = "300";             // Delay receives by 150ms per KB downloaded.            oSession["response-trickle-delay"] = "150";         }                // User-Agent Overrides        if (null != sUA) {            oSession.oRequest["User-Agent"] = sUA;         }        if (m_Japanese) {            oSession.oRequest["Accept-Language"] = "ja";        }        if (m_AutoAuth) {            // Automatically respond to any authentication challenges using the             // current Fiddler user's credentials. You can change (default)            // to a domain\\username:password string if preferred.            //            // WARNING: This setting poses a security risk if remote             // connections are permitted!            oSession["X-AutoAuth"] = "(default)";        }        if (m_AlwaysFresh && (oSession.oRequest.headers.Exists("If-Modified-Since") || oSession.oRequest.headers.Exists("If-None-Match")))        {            oSession.utilCreateResponseAndBypassServer();            oSession.responseCode = 304;            oSession["ui-backcolor"] = "Lavender";        }    }    // This function is called immediately after a set of request headers has    // been read from the client. This is typically too early to do much useful    // work, since the body hasn't yet been read, but sometimes it may be useful.    //    // For instance, see     // http://blogs.msdn.com/b/fiddler/archive/2011/11/05/http-expect-continue-delays-transmitting-post-bodies-by-up-to-350-milliseconds.aspx    // for one useful thing you can do with this handler.    //    // Note: oSession.requestBodyBytes is not available within this function!    // static function OnPeekAtRequestHeaders(oSession: Session) {
        // }    //    // If a given session has response streaming enabled, then the OnBeforeResponse function     // is actually called AFTER the response was returned to the client.    //    // In contrast, this OnPeekAtResponseHeaders function is called before the response headers are     // sent to the client (and before the body is read from the server).  Hence this is an opportune time     // to disable streaming (oSession.bBufferResponse = true) if there is something in the response headers     // which suggests that tampering with the response body is necessary.    //     // Note: oSession.responseBodyBytes is not available within this function!    //    static function OnPeekAtResponseHeaders(oSession: Session) {        if(OnPeekAtResponseHeadersCallback(oSession))            return;        /** 隐藏指定类型的文件 **/        if(m_HideOtherRequest && m_EnableCustomRule && oSession.oResponse != null){            var headers = oSession.oResponse.headers;            if(headers.ExistsAndContains("Content-Type", "text/css")) oSession.Ignore();            else if(headers.ExistsAndContains("Content-Type", "image")) oSession.Ignore();            else if(headers.ExistsAndContains("Content-Type", "script")) oSession.Ignore();            else if(headers.ExistsAndContains("Content-Type", "x-shockwave-flash")) oSession.Ignore();        }                        //FiddlerApplication.Log.LogFormat("Session {0}: Response header peek shows status is {1}", oSession.id, oSession.responseCode);        if (m_DisableCaching) {            oSession.oResponse.headers.Remove("Expires");            oSession.oResponse["Cache-Control"] = "no-cache";        }        if ((bpStatus>0) && (oSession.responseCode == bpStatus)) {            oSession["x-breakresponse"]="status";            oSession.bBufferResponse = true;        }                if ((null!=bpResponseURI) && oSession.uriContains(bpResponseURI)) {            oSession["x-breakresponse"]="uri";            oSession.bBufferResponse = true;        }    }    static function OnBeforeResponse(oSession: Session) {        if(OnBeforeResponseCallback(oSession))            return;        if (m_Hide304s && oSession.responseCode == 304) {            oSession["ui-hide"] = "true";        }    }/*    // This function executes just before Fiddler returns an error that it has     // itself generated (e.g. "DNS Lookup failure") to the client application.    // These responses will not run through the OnBeforeResponse function above.    static function OnReturningError(oSession: Session) {    }*//*    // This function executes after Fiddler finishes processing a Session, regardless    // of whether it succeeded or failed. Note that this typically runs AFTER the last    // update of the Web Sessions UI listitem, so you must manually refresh the Session's    // UI if you intend to change it.    static function OnDone(oSession: Session) {    }*/    // The Main() function runs everytime your FiddlerScript compiles    static function Main() {        var today: Date = new Date();        FiddlerObject.StatusText = " CustomRules.js was loaded at: " + today;        // Uncomment to add a "Server" column containing the response "Server" header, if present        // UI.lvSessions.AddBoundColumn("Server", 50, "@response.server");        // Uncomment to add a global hotkey (Win+G) that invokes the ExecAction method below...        // UI.RegisterCustomHotkey(HotkeyModifiers.Windows, Keys.G, "screenshot");     }    // These static variables are used for simple breakpointing & other QuickExec rules     BindPref("fiddlerscript.ephemeral.bpRequestURI")    public static var bpRequestURI:String = null;    BindPref("fiddlerscript.ephemeral.bpResponseURI")    public static var bpResponseURI:String = null;    BindPref("fiddlerscript.ephemeral.bpMethod")    public static var bpMethod: String = null;    static var bpStatus:int = -1;    static var uiBoldURI: String = null;    static var gs_ReplaceToken: String = null;    static var gs_ReplaceTokenWith: String = null;    static var gs_OverridenHost: String = null;    static var gs_OverrideHostWith: String = null;    // The OnExecAction function is called by either the QuickExec box in the Fiddler window,    // or by the ExecAction.exe command line utility.    static function OnExecAction(sParams: String[]): Boolean {        FiddlerObject.StatusText = "ExecAction: " + sParams[0];        var sAction = sParams[0].toLowerCase();        switch (sAction) {            case "bold":                if (sParams.Length<2) {uiBoldURI=null; FiddlerObject.StatusText="Bolding cleared"; return false;}                uiBoldURI = sParams[1]; FiddlerObject.StatusText="Bolding requests for " + uiBoldURI;                return true;            case "bp":                FiddlerObject.alert("bpu = breakpoint request for uri\nbpm = breakpoint request method\nbps=breakpoint response status\nbpafter = breakpoint response for URI");                return true;            case "bps":                if (sParams.Length<2) {bpStatus=-1; FiddlerObject.StatusText="Response Status breakpoint cleared"; return false;}                bpStatus = parseInt(sParams[1]); FiddlerObject.StatusText="Response status breakpoint for " + sParams[1];                return true;            case "bpv":            case "bpm":                if (sParams.Length<2) {bpMethod=null; FiddlerObject.StatusText="Request Method breakpoint cleared"; return false;}                bpMethod = sParams[1].toUpperCase(); FiddlerObject.StatusText="Request Method breakpoint for " + bpMethod;                return true;            case "bpu":                if (sParams.Length<2) {bpRequestURI=null; FiddlerObject.StatusText="RequestURI breakpoint cleared"; return false;}                bpRequestURI = sParams[1];                 FiddlerObject.StatusText="RequestURI breakpoint for "+sParams[1];                return true;            case "bpa":            case "bpafter":                if (sParams.Length<2) {bpResponseURI=null; FiddlerObject.StatusText="ResponseURI breakpoint cleared"; return false;}                bpResponseURI = sParams[1];                 FiddlerObject.StatusText="ResponseURI breakpoint for "+sParams[1];                return true;            case "overridehost":                if (sParams.Length<3) {gs_OverridenHost=null; FiddlerObject.StatusText="Host Override cleared"; return false;}                gs_OverridenHost = sParams[1].toLowerCase();                gs_OverrideHostWith = sParams[2];                FiddlerObject.StatusText="Connecting to [" + gs_OverrideHostWith + "] for requests to [" + gs_OverridenHost + "]";                return true;            case "urlreplace":                if (sParams.Length<3) {gs_ReplaceToken=null; FiddlerObject.StatusText="URL Replacement cleared"; return false;}                gs_ReplaceToken = sParams[1];                gs_ReplaceTokenWith = sParams[2].Replace(" ", "%20");  // Simple helper                FiddlerObject.StatusText="Replacing [" + gs_ReplaceToken + "] in URIs with [" + gs_ReplaceTokenWith + "]";                return true;            case "allbut":            case "keeponly":                if (sParams.Length<2) { FiddlerObject.StatusText="Please specify Content-Type to retain during wipe."; return false;}                UI.actSelectSessionsWithResponseHeaderValue("Content-Type", sParams[1]);                UI.actRemoveUnselectedSessions();                UI.lvSessions.SelectedItems.Clear();                FiddlerObject.StatusText="Removed all but Content-Type: " + sParams[1];                return true;            case "stop":                UI.actDetachProxy();                return true;            case "start":                UI.actAttachProxy();                return true;            case "cls":            case "clear":                UI.actRemoveAllSessions();                return true;            case "g":            case "go":                UI.actResumeAllSessions();                return true;            case "goto":                if (sParams.Length != 2) return false;                Utilities.LaunchHyperlink("http://www.google.com/search?hl=en&btnI=I%27m+Feeling+Lucky&q=" + Utilities.UrlEncode(sParams[1]));                return true;            case "help":                Utilities.LaunchHyperlink("http://fiddler2.com/r/?quickexec");                return true;            case "hide":                UI.actMinimizeToTray();                return true;            case "log":                FiddlerApplication.Log.LogString((sParams.Length<2) ? "User couldn't think of anything to say..." : sParams[1]);                return true;            case "nuke":                UI.actClearWinINETCache();                UI.actClearWinINETCookies();                 return true;            case "screenshot":                UI.actCaptureScreenshot(false);                return true;            case "show":                UI.actRestoreWindow();                return true;            case "tail":                if (sParams.Length<2) { FiddlerObject.StatusText="Please specify # of sessions to trim the session list to."; return false;}                UI.TrimSessionList(int.Parse(sParams[1]));                return true;            case "quit":                UI.actExit();                return true;            case "dump":                UI.actSelectAll();                UI.actSaveSessionsToZip(CONFIG.GetPath("Captures") + "dump.saz");                UI.actRemoveAllSessions();                FiddlerObject.StatusText = "Dumped all sessions to " + CONFIG.GetPath("Captures") + "dump.saz";                return true;            default:                if (sAction.StartsWith("http") || sAction.StartsWith("www.")) {                    System.Diagnostics.Process.Start(sParams[0]);                    return true;                }                else                {                    FiddlerObject.StatusText = "Requested ExecAction: '" + sAction + "' not found. Type HELP to learn more.";                    return false;                }        }    }            static function SetResponse(oSession: Session, statusCode: Int32, body: String, contentType: String) {        oSession.utilCreateResponseAndBypassServer();        oSession.oResponse.headers.SetStatus(statusCode, "By Fiddler");        if(contentType==null)            contentType="text/html";        contentType=contentType+"; charset=utf-8";        oSession.oResponse["Content-Type"] = contentType;        oSession.oResponse["Date"] = DateTime.Now.ToUniversalTime().ToString("r");        oSession.utilSetResponseBody(body);    }            public static RulesOption("启用自定义规则", "自定义规则")    var m_EnableCustomRule: boolean = true;        /** 隐藏不相关请求（如css、image等） **/    public static RulesOption("隐藏CSS/image等请求", "自定义规则")    var m_HideOtherRequest: boolean = false;        public static RulesOption("强制关闭缓存", "自定义规则")    var m_DisableCache: boolean = false;                   public static RulesOption("隐藏URL黑名单的请求", "自定义规则")    var m_HideByUrlBacklist: boolean = true;                public static RulesOption("仅接受IP白名单的请求", "自定义规则")    var m_DenyWithoutIpWhitelist: boolean = false;                      public static RulesOption("隐藏所有来源请求")    var m_HideAllRequest: boolean = false;    static function MapUrlToFilePath(url: String, rootUrl: String, rootDir: String) {        var idx = url.indexOf(rootUrl);        if(idx < 0)            throw new Error("参数错误：" + rootUrl);        var idxArgs = url.indexOf("?");        var relatPath = url.substring(idx + rootUrl.length, idxArgs > 0 ? idxArgs: undefined);        relatPath = relatPath.replace("/", "\\");        var pSp = relatPath[0] == "\\" ? "" : "\\";        return rootDir + pSp + relatPath;    }}

 

说明：

将OnBeforeRequestCallback方法中的hUrl替换为要劫持的URL路径（可以是部分），将D:\\MyWeb替换为本地文件夹路径。

以代码中路径为例：将来访问http://www.shouxiner.com/MyHome/index.html时，就会转向访问D:\MyWeb\index.html文件里的内容

 

使用方法：

下载FiddlerScript插件并安装，将以上代码粘贴入FiddlerScript保存即可