如何根据文本框文本属性启用/禁用按钮 [英] how to enable/disable a button depending on the textbox text property

问题描述

我在主页面上有一个按钮，在我的内容页面中有一个自由文本框，现在我想在我在自由文本框中输入数据时启用按钮，并在自由文本框中没有数据时禁用



Plz帮帮我......紧急

谢谢

解决方案

你可以用文字更改文本框或文本框丢失焦点事件的事件以查找母版页的控制。



所以你应该在asp.net中使用获得焦点事件...

尝试以下演示，它可能会有所帮助。

 <  < span class =code-leadattribute> input     type   =  text    id   =  uxSearchText    onkeyup   =  changeState（ ）; >  <  输入    type   = < span class =code-keyword> button    id   =  uxSearchButton   值  = 搜索   已禁用  =  已禁用  /  >  
 &l t;   script     type   =  text / javascript >  
  function  changeState（）{
  var  val =  document  .getElementById（'  uxSearchText'）。value; 
  if （val.length> 0）{
  document  .getElementById（< span class =code-string>'  uxSearchButton'）。disabled = ' < span class =code-string>'; 
} 
  else  {
  document  .getElementById（'  uxSearchButton'）。disabled = ' 禁用'; 
} 
} 
 <   /   script  >  
 

如果有的话请告诉我不工作。

还有另一种方法。假设您将Master页面作为Master.master并将子页面作为Default.aspx。请在这些页面中逐步进行以下更改。

在Master页面设计中，您可以使用如下按钮。

< asp：Button ID =uxSearchButtonrunat =serverText =Search/> 

在母版页面的代码后面添加新的公共属性，如下所示。

  public 按钮SearchButton 
 {
  get  
 {
  return   this  .uxSearchButton; 
} 
} 

在Default.aspx的Design部分添加MasterType，如下所示。

<％@ MasterType VirtualPath =〜/ Master.Master％> 

您可以在Default.aspx的Design部分中使用TextBox和脚本，如下所示。 br />

 <   asp：TextBox     ID   =  uxSearchText    runat   =   server >  <   / asp：TextBox  >  
  <   script    类型  =  text / javascript >  
函数changeState（uxSearchText，uxSearchButton）{
 var val = document.getElementById（uxSearchText）.value; 
 if（val.length> 0）{
 document.getElementById（uxSearchButton）.disabled =''; 
} 
 else {
 document.getElementById（uxSearchButton）.disabled ='disabled'; 
} 
} 
 <   / script  >  

在Default.aspx页面的Page_Load事件中添加以下行

 Master.SearchButton.Attributes.Add（  disabled，  disabled）; 
 uxSearchText.Attributes.Add（  onkeyup， string  .Format（  changeState（'{0}'，'{1}'）; ，uxSearchText.ClientID，Master.SearchButton.ClientID））; 
 

现在运行页面，你会得到预期的结果。

i have a button in master page and a Free Text box in my content page,now i want to enable the button when i am entering data in Free Text box and disable when there no data in Free Text box

Plz Help me...its urgent
Thanks

解决方案

you can use text change event of textbox or text box lost focus event to find out master page's conrol.

So you should use got focus event in asp.net ...

Try following demo, it may be helpful.

<input type="text" id="uxSearchText" onkeyup="changeState();"><input type="button" id="uxSearchButton" value="Search" disabled=disabled />
<script type="text/javascript">
    function changeState() {
        var val = document.getElementById('uxSearchText').value;
        if(val.length>0) {
            document.getElementById('uxSearchButton').disabled='';
        }
        else {
            document.getElementById('uxSearchButton').disabled='disabled';
        }
    }
</script>

Let me know if its not working.

There is another way also. Suppose you have Master page as Master.master and child page as Default.aspx. Do following changes in these pages step by step.
In Design of Master page you may have a button as below.

<asp:Button ID="uxSearchButton" runat="server" Text="Search" />

Add new public property in code behind file of Master page as below.

public Button SearchButton
{
    get
    {
        return this.uxSearchButton;
    }
}

In Design part of Default.aspx add MasterType as below.

<%@ MasterType VirtualPath="~/Master.Master" %>

You may have TextBox and script in Design part of Default.aspx as below.

<asp:TextBox ID="uxSearchText" runat="server"></asp:TextBox>
    <script type="text/javascript">
        function changeState(uxSearchText, uxSearchButton) {
            var val = document.getElementById(uxSearchText).value;
            if (val.length > 0) {
                document.getElementById(uxSearchButton).disabled = '';
            }
            else {
                document.getElementById(uxSearchButton).disabled = 'disabled';
            }
        }
    </script>

Add following lines in Page_Load event of Default.aspx page

Master.SearchButton.Attributes.Add("disabled", "disabled");
uxSearchText.Attributes.Add("onkeyup", string.Format("changeState('{0}', '{1}');", uxSearchText.ClientID, Master.SearchButton.ClientID));

Now run the page you will get the result as expected.

这篇关于如何根据文本框文本属性启用/禁用按钮的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！