如果其他情況，為什么輸出會在第二個停止？

我有 html 和 js 代碼，運行它不會在控制臺中顯示錯誤。

我所有的 if 陳述句都是獨立作業的，但是當我將它們全部放在函式中時，我無法讓它們全部作業。

function validate()
{
    var a = document.getElementById("name").value;
    var letters = /^[A-Za-z] $/;
    if(a=="")
    {
        document.getElementById("errName").innerHTML = "Please enter your full name!";
        return false;
    }
    else if ((!a=="")&&(!a.match(letters)))
    {
        document.getElementById("errName").innerHTML = "Not valid!";
        return false;
    }
    else
    {
        document.getElementById("errName").innerHTML = "OK!";
        return true;
    }
    
    var b = document.getElementById("regno").value;
    var Number = /^[0-9] $/;
    var iChars = "!`@#$%^&*() =-[]\\\';,./{}|\":<>?~_"; 
    if(b=="")
    {
        document.getElementById("errRegNo").innerHTML = "Please enter your contact number!";
        return false;
    }
    else if (!b.match(Number) && !b.match(iChars))
    {
        document.getElementById("errRegNo").innerHTML = "Not valid!";
        return false;
    }
    else if(b.match(Number) || b.match(iChars))
    {
        document.getElementById("errRegNo").innerHTML = "OK!";
        return true;
    }
    
    var c = document.getElementById("email").value;
    var mailformat = /^\w ([\.-]?\w )*@\w ([\.-]?\w )*(\.\w{2,3}) $/;
    if(c=="")
    {
        document.getElementById("errEmail").innerHTML = "Please enter your contact number!";
        return false;
    }
    else if ((!c=="")&&(c.match(mailformat)))
    {
        document.getElementById("errEmail").innerHTML = "Not valid!";
        return false;
    }
    else
    {
        document.getElementById("errEmail").innerHTML = "OK!";
        return true;
    }

    var d = document.getElementById("uid").value;
    if(d=="")
    {
        document.getElementById("errUid").innerHTML = "Please enter your user id!";
        return false;
    }
    else if (!d=="")
    {
        document.getElementById("errUid").innerHTML = "OK!";
        return true;
    }
    var e = document.getElementById("password").value;
    var f = document.getElementById("confirm").value;
    if(e=="")
    {
        document.getElementById("errPassword").innerHTML = "Please enter your password!";
        return false;
    }
    else if (!e==f)
    {
        document.getElementById("errPassword").innerHTML = "Not valid!";
        return true;
    }
    else
    {
        document.getElementById("errPassword").innerHTML = "OK!";
        return true;
    }
    
    if(f=="")
    {
        document.getElementById("errPassword").innerHTML = "Please confirm your password!";
        return false;
    }
    else if (!f==e)
    {
        document.getElementById("errPassword").innerHTML = "Not valid!";
        return true;
    }
    else
    {
        document.getElementById("errPassword").innerHTML = "OK!";
        return true;
    }
}

uj5u.com熱心網友回復：

嘗試洗掉

回傳真；

并將其添加到函式的末尾。否則，當達到 return true 時，將不會執行以下代碼。試試下面的代碼。

function validate(){
var a = document.getElementById("name").value;
var letters = /^[A-Za-z] $/;
if(a==""){
    document.getElementById("errName").innerHTML = "Please enter your full name!";
    return false;
}
else if ((!a=="")&&(!a.match(letters))){
    document.getElementById("errName").innerHTML = "Not valid!";
    return false;
}
else{
    document.getElementById("errName").innerHTML = "OK!";
}
var b = document.getElementById("regno").value;
var Number = /^[0-9] $/;
var iChars = "!`@#$%^&*() =-[]\\\';,./{}|\":<>?~_"; 
if(b==""){
    document.getElementById("errRegNo").innerHTML = "Please enter your contact number!";
    return false;
}
else if (!b.match(Number) && !b.match(iChars)){
    document.getElementById("errRegNo").innerHTML = "Not valid!";
    return false;
}
 else if(b.match(Number) || b.match(iChars)){
    document.getElementById("errRegNo").innerHTML = "OK!";
}
var c = document.getElementById("email").value;
var mailformat = /^\w ([\.-]?\w )*@\w ([\.-]?\w )*(\.\w{2,3}) $/;
if(c==""){
    document.getElementById("errEmail").innerHTML = "Please enter your contact number!";
    return false;
}
else if ((!c=="")&&(c.match(mailformat))){
    document.getElementById("errEmail").innerHTML = "Not valid!";
    return false;
}
else{
    document.getElementById("errEmail").innerHTML = "OK!";
}

var d = document.getElementById("uid").value;
if(d==""){
    document.getElementById("errUid").innerHTML = "Please enter your user id!";
    return false;
}
else if (!d==""){
    document.getElementById("errUid").innerHTML = "OK!";
}
var e = document.getElementById("password").value;
var f = document.getElementById("confirm").value;
if(e==""){
    document.getElementById("errPassword").innerHTML = "Please enter your password!";
    return false;
}
else if (!e==f){
    document.getElementById("errPassword").innerHTML = "Not valid!";
    return false;
}
else{
    document.getElementById("errPassword").innerHTML = "OK!";
}
if(f==""){
    document.getElementById("errPassword").innerHTML = "Please confirm your password!";
    return false;
}
else if (!f==e){
    document.getElementById("errPassword").innerHTML = "Not valid!";
    return false;
}
else{
    document.getElementById("errPassword").innerHTML = "OK!";
}
    return true;
}

uj5u.com熱心網友回復：

由于您使用的是return，在任何情況下，如果代碼的起始部分中的條件匹配，它將回傳 true，因此不會執行剩余的代碼。例如：

function validate(){
var a = document.getElementById("name").value;
var letters = /^[A-Za-z] $/;


    if(a==""){
        document.getElementById("errName").innerHTML = "Please enter your full name!";
    
    //if this condition is matched, it will simply return true and it will exit the function.
        return false;
    }
    else if ((!a=="")&&(!a.match(letters))){
        document.getElementById("errName").innerHTML = "Not valid!";
        return false;
    }
    else{
        document.getElementById("errName").innerHTML = "OK!";
        return true;
    }
    
    
    // this wont be executed.
    var b = document.getElementById("regno").value;
    var Number = /^[0-9] $/;
    var iChars = "!`@#$%^&*() =-[]\\\';,./{}|\":<>?~_"

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