if(string_name.length === 0){ // string is empty } ExampleBelow is the example code given, that shows how to use the length property to check the empty string.Open Compiler var str = ''; if(str.length === 0){ document.write('String is empty'); } Following is the out...
An offset of below 0 just starts the search from index 0, and an offset greater than string.length returns false since the search starts from string.length. The String.indexOf() Method The String.indexOf() method is much like the previous includes() method (and it's suitable to be used...
maxLength:function(value, length, errorMsg) {//小于errorMsg=errorMsg||" ";if(value.length > length)returnerrorMsg; }, between:function(value, range, errorMsg) {//大于小于errorMsg=errorMsg||" ";varmin = parseInt(range.split('-')[0]);varmax = parseInt(range.split('-')[1]);if(val...
}//---长度是否对 by lyj ---function notLength(name, length, str) {if(trim(name.value).length !=length) { alert(str); name.focus();returntrue; }returnfalse; }//---固定长度的数字---function notLandN(name, length, str) {if(trim(name.value).length != length ||isNaN(trim(name...
check if the string contains spaces by passing a whitespace string to the method. Since the method returns an index when a whitespace exists, we can check if the value is greater than or equal to zero which returnstrueif there is a whitespace in any index of the string andfalseif ...
if (!String.prototype.includes) { Object.defineProperty(String.prototype, 'includes', { value: function(substring, searchposition) { if (typeof searchposition!== 'number') { searchposition= 0 } if (searchposition+ substring.length > this.length) { return false } else { return this....
importTRTCfrom'trtc-js-sdk'; constcameraList =awaitTRTC.getCameras(); constmicList =awaitTRTC.getMicrophones(); constspeakerList =awaitTRTC.getSpeakers(); consthasCameraDevice = cameraList.length>0; consthasMicrophoneDevice = micList.length>0; ...
String.includes() Method The String.includes()provides the most simple and popular way to check if a string contains a substring in modern JavaScript. It was introduced in ES6 and works in all modern browsers except Internet Explorer. The String.includes() method returns true if the string con...
check.hasLength(thing, value): Returnstrueifthinghas a length property that equalsvalue,falseotherwise. String predicates check.string(thing): Returnstrueifthingis a string,falseotherwise. check.emptyString(thing, options): Returnstrueifthingis the empty string,falseotherwise. ...
Additionally it's possible to check if particular websites are working through this proxy. Websites are checked against specified function, regex or string. //client.jsconstcheckProxy=require('check-proxy').check;checkProxy({testHost:'ping.rhcloud.com',// put your ping server url hereproxyIP...