Question

现在我有(这是来自另一个已经完成的职能)

function validatelength() {
    var length = parseInt(document.getElementById("length").value, 10);
    var lengthError = document.getElementById("lengthError");
    if (isNaN(length) || length < 50 || length > 220) {
        lengthError.innerHTML = ">>Please enter your height<<";
        return false;
    } else {
        lengthError.innerHTML = "";
    }
    return true;
}

这是我的小代码检查字段是否包含一个人的长度。

Now for a text field (name/pre-name/notes) I want this too So far I have

function validatetext() {
    var text = parseInt(document.getElementById("text").value, 10);
    var textError = document.getElementById("textError");
    if (isNaN(text) || text < 50 || text > 220) {
        textError.innerHTML = ">>Please enter text only<<";
        return false;
    } else {
        textError.innerHTML = "";
    }
    return true;
}

Could anyone help me completing the function? Thanks BTW: I can t use jquery. (not allowed to)

Answer 1

使用 regex 以确保在值中只出现字母。

类似的东西

/}[A-Za-z]*$/

应该可以工作。

从线条开始到线条结束从0到无限的时间从A -Z和A

我假设你不想接受任何不是信件的东西

Answer 2

假设 textError 是您重新评价的字符串, 并且应该只使用文本, 我建议 :

if (textError.match(/d/)){
    // there s numbers in this string
}

JS 概念的中继证明。

参考文献:

Answer 3

你看,这个执行可以帮助你整个生命, 如果你是学生, 解释比通常表达方式容易得多。

//In this case I will define here the lower and upper case alphabet
//you can restrict this alphabet to match commas, spaces, or anything else, you just
//need to add them to the var.

var lowercaseLetters = "abcdefghijklmnopqrstuvwxyzáéíóúñü"; 
var uppercaseLetters = "ABCDEFGHIJKLMNOPQRSTUVWXYZÁÉÍÓÚÑ";

//This function will check if an specific letter "c" exist in the previous defined
//alphabet
function isLetter (c) 
{ 
    return( ( uppercaseLetters.indexOf( c ) != -1 ) || 
            ( lowercaseLetters.indexOf( c ) != -1 ) ) 
} 


//this is the Main Method, basically their function is split the Word "s" in all chars
//and check if those chars are defined in 
//the initials vars lowercaseLetters and uppercaseLetters

function isAlphabetic (s) {
   var i; 


    for (i = 0; i < s.length; i+=1) 
    {    
        // Check that current character is letter. 
        var c = s.charAt(i); 

        if (!isLetter(c)) 
        return false; 
    } 
    return true; 
}

现在,要将此函数称为非常容易的函数, 您只需要从输入中捕捉到文本, 然后调用“ 输入( 文本) ” ( 文本), 文本就是所捕捉的文本。

Answer 4

<SCRIPT LANGUAGE="JavaScript">

function checkIt(evt) {
    evt = (evt) ? evt : window.event
    var charCode = (evt.which) ? evt.which : evt.keyCode
    if (!((charCode > 64 && charCode < 91) || (charCode > 96 && charCode < 123))) {
       document.getElementById("lengthError").innerHTML = "This field accepts numbers only."
        return false
    }
    document.getElementById("lengthError").innerHTML = ""
    return true
}

</SCRIPT>

<INPUT TYPE="text" NAME="text" onKeyPress="return checkIt(event)">

友情链接