function validate(){    
    var re = /^[A-Za-z]+$/;
    if(re.test(document.getElementById("textboxID").value))
       alert('Valid Name.');
    else
       alert('Invalid Name.');      
}

检查它的一种方法是遍历字符串并在命中数字时返回true(或false，这取决于您想要什么)。

function checkStringForNumbers(input){
    let str = String(input);
    for( let i = 0; i < str.length; i++){
              console.log(str.charAt(i));
        if(!isNaN(str.charAt(i))){           //if the string is a number, do the following
            return true;
        }
    }
}

Using Regular Expressions with JavaScript. A regular expression is a special text string for describing a search pattern, which is written in the form of /pattern/modifiers where "pattern" is the regular expression itself, and "modifiers" are a series of characters indicating various options.          The character class is the most basic regex concept after a literal match. It makes one small sequence of characters match a larger set of characters. For example, [A-Z] could stand for the upper case alphabet, and \d could mean any digit.

从下面的例子

contains_alphaNumeric«它检查字符串是否包含字母或数字(或)字母和数字。连字符(-)将被忽略。 它检查字符串是否只包含任意序列顺序的字母和数字。

例子:

function matchExpression( str ) {
    var rgularExp = {
        contains_alphaNumeric : /^(?!-)(?!.*-)[A-Za-z0-9-]+(?<!-)$/,
        containsNumber : /\d+/,
        containsAlphabet : /[a-zA-Z]/,

        onlyLetters : /^[A-Za-z]+$/,
        onlyNumbers : /^[0-9]+$/,
        onlyMixOfAlphaNumeric : /^([0-9]+[a-zA-Z]+|[a-zA-Z]+[0-9]+)[0-9a-zA-Z]*$/
    }

    var expMatch = {};
    expMatch.containsNumber = rgularExp.containsNumber.test(str);
    expMatch.containsAlphabet = rgularExp.containsAlphabet.test(str);
    expMatch.alphaNumeric = rgularExp.contains_alphaNumeric.test(str);

    expMatch.onlyNumbers = rgularExp.onlyNumbers.test(str);
    expMatch.onlyLetters = rgularExp.onlyLetters.test(str);
    expMatch.mixOfAlphaNumeric = rgularExp.onlyMixOfAlphaNumeric.test(str);

    return expMatch;
}

// HTML Element attribute's[id, name] with dynamic values.
var id1 = "Yash", id2="777", id3= "Yash777", id4= "Yash777Image4"
    id11= "image5.64", id22= "55-5.6", id33= "image_Yash", id44= "image-Yash"
    id12= "_-.";
console.log( "Only Letters:\n ", matchExpression(id1) );
console.log( "Only Numbers:\n ", matchExpression(id2) );
console.log( "Only Mix of Letters and Numbers:\n ", matchExpression(id3) );
console.log( "Only Mix of Letters and Numbers:\n ", matchExpression(id4) );

console.log( "Mixed with Special symbols" );
console.log( "Letters and Numbers :\n ", matchExpression(id11) );
console.log( "Numbers [-]:\n ", matchExpression(id22) );
console.log( "Letters :\n ", matchExpression(id33) );
console.log( "Letters [-]:\n ", matchExpression(id44) );

console.log( "Only Special symbols :\n ", matchExpression(id12) );

把:

Only Letters:
  {containsNumber: false, containsAlphabet: true, alphaNumeric: true, onlyNumbers: false, onlyLetters: true, mixOfAlphaNumeric: false}
Only Numbers:
  {containsNumber: true, containsAlphabet: false, alphaNumeric: true, onlyNumbers: true, onlyLetters: false, mixOfAlphaNumeric: false}
Only Mix of Letters and Numbers:
  {containsNumber: true, containsAlphabet: true, alphaNumeric: true, onlyNumbers: false, onlyLetters: false, mixOfAlphaNumeric: true}
Only Mix of Letters and Numbers:
  {containsNumber: true, containsAlphabet: true, alphaNumeric: true, onlyNumbers: false, onlyLetters: false, mixOfAlphaNumeric: true}
Mixed with Special symbols
Letters and Numbers :
  {containsNumber: true, containsAlphabet: true, alphaNumeric: false, onlyNumbers: false, onlyLetters: false, mixOfAlphaNumeric: false}
Numbers [-]:
  {containsNumber: true, containsAlphabet: false, alphaNumeric: false, onlyNumbers: false, onlyLetters: false, mixOfAlphaNumeric: false}
Letters :
  {containsNumber: false, containsAlphabet: true, alphaNumeric: false, onlyNumbers: false, onlyLetters: false, mixOfAlphaNumeric: false}
Letters [-]:
  {containsNumber: false, containsAlphabet: true, alphaNumeric: true, onlyNumbers: false, onlyLetters: false, mixOfAlphaNumeric: false}
Only Special symbols :
  {containsNumber: false, containsAlphabet: false, alphaNumeric: false, onlyNumbers: false, onlyLetters: false, mixOfAlphaNumeric: false}

java正则表达式模式匹配。

如果我没记错的话，这个问题需要“contains number”，而不是“is number”。所以:

function hasNumber(myString) {
  return /\d/.test(myString);
}

要测试任何字符是否为数字，无需过度修饰❓，可根据需要进行调整。

const s = "EMA618" 函数hasInt(我){ 设I = 1,a = me.split("")，b = ""，c = ""; a.forEach(函数(e) { 如果(! isNaN (e)) { console.log(' contains NUMBER«${e}»AT POSITION ${a.indexOf(e)} => TOTAL COUNT ${i} ') C += e 我+ + } else {b += e} }) console.log('字符串是«${b}»，数字是«${c}»') If (i === 0){ 返回假 //返回b }其他{ 还真 //返回+c ｝ ｝ hasInt (s)

你可以使用javascript来做到这一点。不需要Jquery或Regex

function isNumeric(n) 
{
  return !isNaN(n);
}