Vue Js Check if String is Empty:In Vue.js, you can check if a string is empty using the v-if directive along with the trim method. The trim method removes any whitespace from the beginning and end of the string, leaving only its content. You can then use
functiontestuser(){vari=document.getElementByIdx_x("aa");if(i.value=="null"){alert("请登录后再发表留言!")returnfalse;}else{alert(i.value)returntrue;}} 参考五: 方法一: 使用trim() 代码语言:javascript 代码运行次数:0 运行 AI代码解释 /* 使用String.trim()函数,来判断字符串是否全为空*/fu...
/* 使用正则表达式来判断字符串是否全为空 */functionkongge2(test) {if(test.match(/^\s+$/)){console.log("all space or \\n"); }if(test.match(/^[ ]+$/)){console.log("all space") }if(test.match(/^[ ]*$/)){console.log("all space or empty") }if(test.match(/^\s*$/))...
function isEmpty(obj){ if(typeof obj == "undefined" || obj == null || obj == ""){ return true; }else{ return false; } } 1. 2. 3. 4. 5. 6. 7. 参考二: if (variable1 !== null || variable1 !== undefined || variable1 !== '') { var variable2 = variable1; } 1...
function checkForm(){ var isPass = true; //过滤字符串 if(!(checkData.isEmptySpan("filterStr") && checkData.filterStrSpan('filterStr','#'))) { isPass = false; } //检查url if(!(checkData.isEmptySpan("isURL") && checkData.isURLSpan('isURL'))) ...
示例代码: public static void main(String[] args) { Map map = new HashMap(); System.out.println("map为空:" + map.isEmpty()); //加入元素 map.put("1"..., "1"); System.out.println("map为空:" + map.isEmpty()); } 输出结果: 这里是用isEmpty()方法来做判断,其实和map.size.....
If it passed, this will be an empty stringAlso note that if you only have one argument, then the first argument to the apiCheck function can simply be the checker function. For example:apiCheck(apiCheck.bool, arguments);The second argument can either be an arguments-like object or an ...
Pass an empty string "" to enable, or a non-empty string to set the debug suffix. domprops (default: false)— Use true to allow the mangling of properties commonly found in Document Object Model. Not recommended to override this setting. globals (default: false)— Use true to mangle ...
'' (empty string) false 函数构造函数,如new Number和new Boolean都是真值。36. 【typeof】下面代码的输出是什么? console.log(typeof typeof 1); A: "number" B: "string" C: "object" D: "undefined" 答案: Btypeof 1 返回"number".typeof "number" 返回"string"37...
letcr =newcors({//不允许referer为空allowEmptyReferer:false,//允许referer为空的路由分组,//分组名称是自定义的,参考titbit框架的路由分组功能。//此功能主要用于在API开发中还要兼顾页面的服务上。emptyRefererGroup: ['@webapp','@pages'],allow: [//默认的字符串形式表示origin跨域和referer外链接引用都被允...