Error adding ONCLICK event to button

kostarcn

.cs file
private void Page_Load (object sender, System.EventArgs e)
{
btnLogin.Attributes.Add ("onclick", "checkUserName ();");
}

html code:
<script language = "javascript" src = "ScriptFiles / BBS_JScript.js"> </ script>


Code in BBS_JScript.js:

function checkUserName ()
{
var isRight;
var userName = document.all ("txtUserName"). value;
var userNameLen = userName.length;
if (userName == "")
    {
       alert ("The username cannot be empty!");
       isRight = false;
    }
    else
    {
if (userNameLen> 6&&userNameLen <= 16)
{
isRight = true;
}
else
{
alert ("The username is between 6 and 16 characters long!");
isRight = false;
}
}
    return isRight;
}

"Runtime error" and "Syntax error" occur when the page loads.
I put
else
{
alert ("The username is between 6 and 16 characters long!");
isRight = false;
}
There will be no problem if you delete it, I really do n’t understand why, please master, thank you

zhouyin1981

Give it a try
btnLogin.Attributes.Add ("onclick", "return checkUserName ();");

3521565

alert ("The username is between 6 and 16 characters long!");
to
alert ('The username is between 6 and 16 characters in length!');
Try

5954979

Bobo was right. In addition, you can write return checkUserName (); directly to the OnClientClick property of that control.

摩羯可乐

You don't return this function

vampire_66

Renamed
btnLogin.Attributes.Add ("onclick", "return checkUserName ();");
It's ok

暗中的手

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