Eplan ppe pro-panel electric fluid P8等多个最新2.4中文版本的安装,都是使用相同的虚拟驱动MultiKey,还是只有win32位的安装包,不过支持64位操作系统的安装. Eplan PPE Pro-panel Electric fluid P8 2.4的安装和以往版本的安装方法大致一样.下面具体的来说下. 如果电脑上没有安装过net framework 4.0,需要先安装.这个直接百度一下,从百度软件中心下载就行.安装完net framework 4.0以后
当运行程序时,会出现如下警告: Warning: strftime(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still ge
JavaScript中会经常遇到一个操作符:! 这是一个布尔操作符,用于将操作的值强制转换为布尔值并取反.常用场景如下: //条件判断中使用 var a; var b=null; if(!a){ console.log("a是假的"); } if(!b){ console.log("b是假的"); } //操作布尔值 var c = false; var d = !c;//d === true; //IIFE(自执行函数.立即执行函数:Immediately-Inv
var foo; alert(!foo);//undefind情况下或者null,一个感叹号返回的是true; alert(!goo);//undefind情况下,一个感叹号返回的也是true; 但是这里会报undefind的错误 var o={flag:true}; var test=!!o.flag;//等效于var test=o.flag||false; alert(test); //返回true var test2=!!o.flag1;//当里面没有对象时 alert(test2);//
The most interesting addition to Ruby 2.3.0 is the Safe Navigation Operator(&.). A similar operator has been present in C# and Groovy for a long time with a slightly different syntax - ?.. So what does it do? Scenario Imagine you have an account that