在项目中遇到一个这样的问题。即：进行登录以后才引进并执行一个外部的js文件。代码如下：
//动态引进js,登录成功后引入holdSession.js ?function loadScript(url, callback) { ???var script = document.createElement("script"); ???script.type = "text/javascript"; ???if(typeof(callback) != "undefined") { ?????if(script.readyState) { ???????script.onreadystatechange = function() { ?????????if(script.readyState == "loaded" || script.readyState == "complete") { ???????????script.onreadystatechange = null; ???????????callback(); ?????????} ???????}; ?????} else { ???????script.onload = function() { ?????????callback(); ???????}; ?????} ???}; ???script.src = url; ???document.body.appendChild(script); ?}//点击登陆function fun_login(_type) { ?//检查录入项目: ?var err = checkLogin(); ?if(err) { ???alert(err); ???return; ?} ?var formData = { ???"loginType": _type, ???"loginName": $(".login-right input[name=‘loginname‘]").val(), ???"password": $(".login-right input[name=‘password‘]").val() ?}; ?$.ajax({ ???type: ‘post‘, ???url: "/dp/spirit/login", ???data: formData, ???dataType: ‘json‘, ???success: function(data) { ?????if(data.returnCode == "00") { ???????isLogin = "1"; ???????var memberObjStr = JSON.stringify(data.memberInfo); ???????sessionStorage.setItem("cgpt_memberInfo", memberObjStr); ???????sessionStorage.setItem("cgpt_pwd", $(".login-right input[name=‘password‘]").val()); ???????$("#signBox").html(""); ???????$("#signModal").modal("hide"); ???????fillMemberMes(memberObjStr); ???????loadScript("/dp/cgpt/js/holdSession.js", function() { ?????????//加载,并执行回调函数 ???????}); ?????} else { ???????alert("登录失败:" + data.messageInfo); ?????} ???}, ???error: function(XMLHttpRequest, textStatus, errorThrown) { //失败回调函数 ?????var m = "系统错误：\nstatu=" + XMLHttpRequest.status + "\nreadyState=" + XMLHttpRequest.readyState + "\ntext=" + textStatus + "\nerrThrown=" + errorThrown; ?????alert(m); ???} ?});动态引进js文件
原文地址：https://www.cnblogs.com/TigerZhang-home/p/8985611.html