回发多步骤表单时，未加载当前选定的选项卡。 JavaScript 和 asp.net

Question

我有来自 W3schools.com 的简单多步骤表单模板。 在步骤表单的第二个选项卡中，单击服务器端按钮（asp 按钮），然后页面回发并加载第一个选项卡表单（第一步）。 因此我尝试了在回发后加载相同标签的方法。 那还不成功。 我希望您为我的代码提供解决方案。

Javascript：

    <script>
        var currentTabnew;
       var last = sessionStorage.getItem('tab');

        // Current tab is set to be the first tab (0)
        if (last==0 ||last==null ) {
            currentTabnew = 0;
        }
        else {
            currentTabnew =  last;
        }
showTab(currentTabnew); // Display the current tab

function showTab(n) {
  // This function will display the specified tab of the form ...
  var x = document.getElementsByClassName("tab");
  x[n].style.display = "block";
  // ... and fix the Previous/Next buttons:
  if (n == 0) {
    document.getElementById("prevBtn").style.display = "none";
  } else {
    document.getElementById("prevBtn").style.display = "inline";
  }
  if (n == (x.length - 1)) {
    document.getElementById("nextBtn").innerHTML = "Submit";
  } else {
    document.getElementById("nextBtn").innerHTML = "Next";
  }
  // ... and run a function that displays the correct step indicator:
  fixStepIndicator(n)
}

function nextPrev(n) {
  // This function will figure out which tab to display
  var x = document.getElementsByClassName("tab");
  // Exit the function if any field in the current tab is invalid:
  if (n == 1 && !validateForm()) return false;
  // Hide the current tab:
  x[currentTab].style.display = "none";
  // Increase or decrease the current tab by 1:
  currentTab = currentTab + n;
  // if you have reached the end of the form... :
  if (currentTab >= x.length) {
    //...the form gets submitted:
      
    document.getElementById("regForm").submit();
    return false;
  }
  // Otherwise, display the correct tab:
    //sessionStorage.setItem('tab');
    showTab(currentTab);
    
}

function validateForm() {
  // This function deals with validation of the form fields
  var x, y, i, valid = true;
  x = document.getElementsByClassName("tab");
  y = x[currentTab].getElementsByTagName("input");
  // A loop that checks every input field in the current tab:
  for (i = 0; i < y.length; i++) {
    // If a field is empty...
    if (y[i].value == "") {
      // add an "invalid" class to the field:
      y[i].className += " invalid";
      // and set the current valid status to false:
      valid = false;
    }
  }
  // If the valid status is true, mark the step as finished and valid:
  if (valid) {
    document.getElementsByClassName("step")[currentTab].className += " finish";
  }
  return valid; // return the valid status
}

function fixStepIndicator(n) {
  // This function removes the "active" class of all steps...
  var i, x = document.getElementsByClassName("step");
  for (i = 0; i < x.length; i++) {
    x[i].className = x[i].className.replace(" active", "");
  }
  //... and adds the "active" class to the current step:
  x[n].className += " active";
}
        </script>

我的.aspx 代码：

<asp:Content ID="Content1" ContentPlaceHolderID="ContentPlaceHolder1" runat="server">
    <link href="https://fonts.googleapis.com/css?family=Raleway" rel="stylesheet">
<style>
* {
  box-sizing: border-box;
}

#regForm {
  background-color: #ffffff;
  margin: 100px auto;
  font-family: Raleway;
  padding: 40px;
  width: 70%;
  min-width: 300px;
      margin-bottom: 5px;


}

h1 {
  text-align: center;  
}

input {
  padding: 10px;
  width: 100%;
  font-size: 17px;
  font-family: Raleway;
  border: 1px solid #aaaaaa;
}

/* Mark input boxes that gets an error on validation: */
input.invalid {
  background-color: #ffdddd;
}

/* Hide all steps by default: */
.tab {
  display: none;
}

/* Make circles that indicate the steps of the form: */
.step {
  height: 15px;
  width: 15px;
  margin: 0 2px;
  background-color: #bbbbbb;
  border: none;  
  border-radius: 50%;
  display: inline-block;
  opacity: 0.5;
}

.step.active {
  opacity: 1;
}

/* Mark the steps that are finished and valid: */
.step.finish {
  background-color: #04AA6D;
}
</style>

    <div id="regForm" class="shadow">
  <h3>Registration Form</h3>
<br />
  <div class="tab"><h5>Personal Details</h5> <br />
      <div class="row">
        
<div class="col">
<div class="mb-3"><asp:textbox runat="server" type="text" class="form-control"  placeholder="Full Name"></asp:textbox></div>  
<div class="mb-3"><asp:textbox runat="server" type="text" class="form-control"  placeholder="Surename"></asp:textbox></div>
<div class="mb-3"><asp:textbox runat="server" type="date" class="form-control"  placeholder="Date of Birth"></asp:textbox></div>
<div class="mb-3"><asp:dropdownlist runat="server"  class="form-control">
    <asp:ListItem Value=""  selected hidden>Civil Status</asp:ListItem>
    <asp:ListItem Value="CV1">Single</asp:ListItem>
    <asp:ListItem Value="CV2">Married</asp:ListItem>
    <asp:ListItem Value="CV3">Widowed</asp:ListItem>
    <asp:ListItem Value="CV4">Divorced</asp:ListItem>
    <asp:ListItem Value="CV5">Separated</asp:ListItem>
    </asp:dropdownlist> </div>
    <div class="mb-3"><asp:textbox runat="server" type="text" class="form-control"  placeholder="Land Phone"></asp:textbox></div>
<div class="mb-3"><asp:textbox runat="server" type="texxt" class="form-control"  placeholder="Address" TextMode="MultiLine"></asp:textbox></div>
<div class="mb-3"><asp:textbox runat="server" type="text" class="form-control"  placeholder="E-mail"></asp:textbox></div>

</div>
<div class="col">
<div class="mb-3"><asp:textbox runat="server" type="text" class="form-control"  placeholder="Other Name"></asp:textbox></div>
<div class="mb-3"><asp:textbox runat="server" type="text" class="form-control"  placeholder="NIC"></asp:textbox></div>
<div class="mb-3"><asp:dropdownlist runat="server"  class="form-control">
    <asp:ListItem Value=""  selected hidden>Gender</asp:ListItem>
    <asp:ListItem Value="G1">Male</asp:ListItem>
    <asp:ListItem Value="G0">Female</asp:ListItem>
    </asp:dropdownlist> </div>
<div class="mb-3"><asp:dropdownlist runat="server"  class="form-control">
    <asp:ListItem Value=""  selected hidden>Religion</asp:ListItem>
    <asp:ListItem Value="R1">Christianity</asp:ListItem>
    <asp:ListItem Value="R2">Hinduism</asp:ListItem>
    <asp:ListItem Value="R3">Buddhism</asp:ListItem>
    <asp:ListItem Value="R4">Islam</asp:ListItem>
    </asp:dropdownlist> </div>
    <div class="mb-3"><asp:textbox runat="server" type="text" class="form-control"  placeholder="Mobile"></asp:textbox></div>
<div class="mb-3"><asp:dropdownlist runat="server"  class="form-control">
    <asp:ListItem Value=""  selected hidden>District</asp:ListItem>
 <asp:ListItem Value="CV1"> Jaffna  </asp:ListItem>
 <asp:ListItem Value="CV1"> Kilinochchi </asp:ListItem>
 <asp:ListItem Value="CV1"> Mannar  </asp:ListItem>
 <asp:ListItem Value="CV1"> Mullaitivu  </asp:ListItem>
 <asp:ListItem Value="CV1"> Vavuniya    </asp:ListItem>
 <asp:ListItem Value="CV1"> Puttalam    </asp:ListItem>
 <asp:ListItem Value="CV1"> Kurunegala  </asp:ListItem>
 <asp:ListItem Value="CV1"> Gampaha </asp:ListItem>
 <asp:ListItem Value="CV1"> Colombo </asp:ListItem>
 <asp:ListItem Value="CV1"> Kalutara    </asp:ListItem>
 <asp:ListItem Value="CV1"> Anuradhapura    </asp:ListItem>
 <asp:ListItem Value="CV1"> Polonnaruwa </asp:ListItem>
 <asp:ListItem Value="CV1"> Matale  </asp:ListItem>
 <asp:ListItem Value="CV1"> Kandy   </asp:ListItem>
 <asp:ListItem Value="CV1"> Nuwara Eliya    </asp:ListItem>
 <asp:ListItem Value="CV1"> Kegalle </asp:ListItem>
 <asp:ListItem Value="CV1"> Ratnapura   </asp:ListItem>
 <asp:ListItem Value="CV1"> Trincomalee </asp:ListItem>
 <asp:ListItem Value="CV1"> Batticaloa  </asp:ListItem>
 <asp:ListItem Value="CV1"> Ampara  </asp:ListItem>
 <asp:ListItem Value="CV1"> Badulla </asp:ListItem>
 <asp:ListItem Value="CV1"> Monaragala  </asp:ListItem>
 <asp:ListItem Value="CV1"> Hambantota  </asp:ListItem>
 <asp:ListItem Value="CV1"> Matara  </asp:ListItem>
 <asp:ListItem Value="CV1"> Galle   </asp:ListItem>

    </asp:dropdownlist> </div>
<div class="mb-3"><asp:textbox runat="server" type="text" class="form-control"  placeholder="Nearest Police Station"></asp:textbox></div>

</div>
      </div>
  </div>
  <div class="tab">
      <h5>Educational Qualification </h5> <br />
<div class="row">
    <div class="mb-3"><asp:dropdownlist runat="server"  class="form-control">
    <asp:ListItem Value=""  selected hidden>Select Highest Education...</asp:ListItem>
    <asp:ListItem Value="R1">Grade 8</asp:ListItem>
    <asp:ListItem Value="R2">O/L</asp:ListItem>
    <asp:ListItem Value="R3">A/L</asp:ListItem>
    <asp:ListItem Value="R4">Degree</asp:ListItem>
     <asp:ListItem Value="R2">Doctor</asp:ListItem>
    <asp:ListItem Value="R3">PHD</asp:ListItem>
    <asp:ListItem Value="R4">Not Mentioned</asp:ListItem>
    </asp:dropdownlist> </div>
    </div>
      <br />
        <h5>Professional Qualification</h5>
      <br />
<div class="row">
    <asp:gridview ID="Gridview1" runat="server" ShowFooter="True" 
                             AutoGenerateColumns="False" CssClass="table table-hover" BorderStyle="None">
        <Columns>
        <asp:TemplateField HeaderText="Institute">
            <ItemTemplate>
                <asp:TextBox ID="TextBox1" runat="server"   class="form-control" ></asp:TextBox>
            </ItemTemplate>
        </asp:TemplateField>
        <asp:TemplateField HeaderText="Qualification">
            <ItemTemplate>
                <asp:TextBox ID="TextBox2" runat="server"  class="form-control" ></asp:TextBox>
            </ItemTemplate>
        </asp:TemplateField>
        <asp:TemplateField HeaderText="Duration">
            <ItemTemplate>
                 <asp:TextBox ID="TextBox3" runat="server"  class="form-control" ></asp:TextBox>
            </ItemTemplate>
            <FooterStyle HorizontalAlign="Right" />
            <FooterTemplate>
                 
                 <input id="btnAdd" type="button" style="width:200px;" class="btn btn-info" value="Add" onclick="addRowToTable(<%= Gridview1.ClientID %>)"/>
            </FooterTemplate>
        </asp:TemplateField>
            <asp:CommandField HeaderText="sdfsd" />
        </Columns>
</asp:gridview>
    <asp:button runat="server" text="Button" />
</div>
  </div>
        
  <div class="tab">Birthday:
    <p><input placeholder="dd" oninput="this.className = ''" name="dd"></p>
    <p><input placeholder="mm" oninput="this.className = ''" name="nn"></p>
    <p><input placeholder="yyyy" oninput="this.className = ''" name="yyyy"></p>
  </div>
  <div class="tab">Login Info:
    <p><input placeholder="Username..." oninput="this.className = ''" name="uname"></p>
    <p><input placeholder="Password..." oninput="this.className = ''" name="pword" type="password"></p>
  </div>
  <div style="overflow:auto;">
    <div style="float:right;">
      <button type="button" id="prevBtn" onclick="nextPrev(-1)" class="btn btn-secondary">Previous</button>
      <button type="button" id="nextBtn" onclick="nextPrev(1)" class="btn btn-primary">Next</button>
    </div>
  </div>
  <!-- Circles which indicates the steps of the form: -->
  <div style="text-align:center;margin-top:40px;">
    <span class="step"></span>
    <span class="step"></span>
    <span class="step"></span>
    <span class="step"></span>
  </div></div>
    <div style="text-align:center;">
    <p class="mt-5 mb-3 text-muted">&copy;2021 SLFEA</p>
       <p class="mb-3 text-muted" style="font-size:small;">Designed by Dockyard Total Solutions Pvt Ltd</p></div>
    <script>
        function addRowToTable(containerId) {
            // Get a reference to the table/GridView...
            var tableRef = document.getElementById('<%= Gridview1.ClientID %>');

            // Get the index of the current last row...
            var lastRow = tableRef.rows.length;

            // Add a row (<tr>) to the table/GridView...
            var newRow = tableRef.insertRow(lastRow - 1);

            // Add a cell (<td>) to the row...
            var newCell = newRow.insertCell(0);
            var newCell1 = newRow.insertCell(1);
            var newCell2 = newRow.insertCell(2);

            // Create a TextBox...
            var controlRef = document.createElement('input');
            controlRef.type = 'text';
            controlRef.id = containerId + '_TextBox' + lastRow;
            controlRef.name = controlRef.id;
            controlRef.size = 20;

             var controlRef1 = document.createElement('input');
            controlRef.type = 'text';
            controlRef.id = '01' + '_TextBox' + lastRow;
            controlRef.name = controlRef.id;
            controlRef.size = 20;

            var controlRef2 = document.createElement('input');
            controlRef.type = 'text';
            controlRef.id = '02' + '_TextBox' + lastRow;
            controlRef.name = controlRef.id;
            controlRef.size = 20;


            // Add the TextBox to the cell...
            newCell.appendChild(controlRef);
            newCell1.appendChild(controlRef1);
            newCell2.appendChild(controlRef2);
        }
    </script>
</asp:Content>

Answer 1

谢谢大家。 因为没有考虑我的问题。

这对我有用。

<script>
    var currentTab;
    var newCurrentTab = sessionStorage.getItem("lastTab");
    if (newCurrentTab == 0 || newCurrentTab == null) {
        currentTab = 0;
    } else {
        currentTab = newCurrentTab;
    }
    showTab(currentTab); // Display the current tab

    function showTab(n) {
        // This function will display the specified tab of the form ...
        var x = document.getElementsByClassName("tab");
        x[n].style.display = "block";
        // ... and fix the Previous/Next buttons:
        if (n == 0) {
            document.getElementById("prevBtn").style.display = "none";
        } else {
            document.getElementById("prevBtn").style.display = "inline";
        }
        if (n == x.length - 1) {
            document.getElementById("nextBtn").innerHTML = "Submit";
        } else {
            document.getElementById("nextBtn").innerHTML = "Next";
        }
        // ... and run a function that displays the correct step indicator:
        fixStepIndicator(n);
    }

    function nextPrev(n) {
        // This function will figure out which tab to display
        var x = document.getElementsByClassName("tab");
        // Exit the function if any field in the current tab is invalid:
        if (n == 1 && !validateForm()) return false;
        // Hide the current tab:
        x[currentTab].style.display = "none";
        // Increase or decrease the current tab by 1:
        currentTab = currentTab + n;
        // if you have reached the end of the form... :
        if (currentTab >= x.length) {
            //...the form gets submitted:
            document.getElementById("regForm").submit();
            return false;
        }
        // Otherwise, display the correct tab:
        sessionStorage.setItem("lastTab", currentTab);

        showTab(currentTab);
    }

    function validateForm() {
        // This function deals with validation of the form fields
        var x,
            y,
            i,
            valid = true;
        x = document.getElementsByClassName("tab");
        y = x[currentTab].getElementsByTagName("input");
        // A loop that checks every input field in the current tab:
        for (i = 0; i < y.length; i++) {
            // If a field is empty...
            if (y[i].value == "") {
                // add an "invalid" class to the field:
                y[i].className += " invalid";
                // and set the current valid status to false:
                valid = false;
            }
        }
        // If the valid status is true, mark the step as finished and valid:
        if (valid) {
            document.getElementsByClassName("step")[currentTab].className += " finish";
        }
        return valid; // return the valid status
    }

    function fixStepIndicator(n) {
        // This function removes the "active" class of all steps...
        var i,
            x = document.getElementsByClassName("step");
        for (i = 0; i < x.length; i++) {
            x[i].className = x[i].className.replace(" active", "");
        }
        //... and adds the "active" class to the current step:
        x[n].className += " active";
    }
</script>