In the project, you need to verify that the input string is empty, including spaces, and do not like to use regular, so I think of JS's indexOf function, the IndexOf () method returns the position of a specified string value in the first occurrence of the string, and if the string value to retrieve does not appear, the method returns- 1.
Syntax: Stringobject.indexof (searchvalue,fromindex), Searchvalue required, Fromindex: Optional parameter, where to start retrieving in the string. Its legal value is 0 to stringobject.length-1. If this argument is omitted, it is retrieved from the first character of the string.
1 Demo:2 3 function CheckValue () {4 5 varEnumvalue = document.getElementById ('Txtenumvalue'). Value;6 7 if(Enumvalue.indexof (" ") >=0) {8 9Alert"content cannot contain spaces! ");Ten One return false; A - } - the if(enumvalue=="") { - -Alert"Please enter the content! "); - + return false; - + } A at}
JavaScript does not validate that the input string is empty (contains spaces)