javascript check if value has at least 2 or more words

问题

I have a field that you enter your name in and submit it. I would like the receive peoples first and last names and to do this i need to check if the value contains at least 2 words. This is what I am using right now but it doesn't seem to work.

function validateNameNumber(name) {
    var NAME = name.value;
    var matches = NAME.match(/\b[^\d\s]+\b/g);
    if (matches && matches.length >= 2) {
        //two or more words
        return true;
    } else {
        //not enough words
        return false;
    }
}

回答1:

str.trim().indexOf(' ') != -1 //there is at least one space, excluding leading and training spaces

回答2:

You could use the String.Split() method:

function validateNameNumber(name) {
    var NAME = name.value;
    var values = name.split(' ').filter(function(v){return v!==''});
    if (values.length > 1) {
        //two or more words
        return true;
    } else {
        //not enough words
        return false;
    }
}

If you were to pass "John Doe" as the name value, values would equal {"john", "doe"}

http://www.w3schools.com/jsref/jsref_split.asp

Edit: Added filter to remove empty values. Source: remove an empty string from array of strings - JQuery

回答3:

The easy solution (not 100% reliable, since "foo " returns 4, as @cookiemonster mentioned):

var str = "Big Brother";
if (str.split(" ").length > 1) {
    // at least 2 strings
}

The better solution:

var str = "Big Brother";
var regexp = /[a-zA-Z]+\s+[a-zA-Z]+/g;
if (regexp.test(str)) {
    // at least 2 words consisting of letters
}

回答4:

Probably not the best solution overall (see the other answers), but one that shows how to count the number of times a regexp matches a string:

function validateNameNumber(name) {
    var nameValue = name.value;
    var regexp = /\b[^\d\s]+\b/g;
    var count = 0;
    while (regexp.exec(nameValue)) ++count;
    if (count >= 2) {
        //two or more words
        return true;
    } else {
        //not enough words
        return false;
    }
}

回答5:

Change this line from your snippet

var matches = NAME.match(/\b[^\d\s]+\b/g);

to this

var matches = NAME.match(/\S+/g);

or to this, if numbers should be excluded

var matches = NAME.match(/\b([a-z]+)\b/gi);

Side (funny) note: Your snippet works just fine. Check the jsBin

回答6:

I would just check for whitespace by running a for loop.

var correctFormat = false;
for (var i = 0; i = i < name.length; i++) {
    if (name[i] === " ") {
       correctFormat = true;
    }
}
if (correctFormat === false) {
    alert("You entered an invalid name");
    return false;
} else {
    return true;
}

If the name doesn't have a space, knowing that there is a space between the first and last name, it would alert("You entered an invalid name");

来源：https://stackoverflow.com/questions/25344603/javascript-check-if-value-has-at-least-2-or-more-words

标签

javascript

regex

string

input