Question

我有2个文本框和按钮的页面。当我按下按钮时, 服务器上会出现一些事件。但我需要检查是否文本框是空的大小写。所以我在客户点击 \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\

 function Button1_javaEvent() {
        var flag = false;
        var message_str = "";
        if (main_form.Text_login.value == "") {
                message_str += "Enter the login";
                message_str += "
";
                flag = true;
            }
         if (main_form.Password_login.value == "") {
                message_str += "Enter the password";
                flag = true;
             }
             if (flag == true) {
                 alert(message_str);
             }
             else {                  
                   ????????????         
             }
         }

Answer 1

使用以下代码 :

onclientclick="return Button1_javaEvent()"

从 button1_javaEvent () 函数返回真实/虚假, 如果 Button1_javaEvent () 返回真实, 否则返回后不会发生。

< a href=>"http://www.w3schools.com/aspnet/prop_webcontrol_linkbutton_onclic kick.asp" rel="nofollow" > 参考在线样本测试

Answer 2

在您的 javascript 函数中, 如果您想要返回后返回为真, 如果您不想返回后返回为假返回为真。

像这样:

function Button1_javaEvent() {
    var flag = false;
        var message_str = "";
        if (main_form.Text_login.value == "") {
                message_str += "Enter the login";
                message_str += "
";
                flag = true;
    }

    if (main_form.Password_login.value == "") {
                message_str += "Enter the password";
                flag = true;
    }

    if (flag == true) {
        alert(message_str);
    }

    return !flag;
}

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