ASP.NET - 服务器控件

服务器控件是服务器可以理解的标签。

Classic ASP 的局限性

下面列出的代码是从上一节中拷贝的：

<html>


Hello CodeW3C.com!

<p><%Response.Write(now())%></p>
</body>
</html>

上面的代码能够反映出 Classic ASP 的局限性：代码块必须放置在需要进行输出的位置。

通过 Classic ASP，我们是无法将可执行代码与 HTML 本身进行分离的。这使得页面难以阅读，也难以维护。

ASP.NET - 服务器控件

通过服务器控件，ASP.NET 已经解决了上面所描述的“意大利面条式代码”的问题。

服务器控件是可被服务器理解的标签。

有三种类型的服务器控件：

  • HTML 服务器控件 - 传统的 HTML 标签
  • Web 服务器控件 - 新的 ASP.NET 标签
  • Validation 服务器控件 - 用于输入验证

ASP.NET - HTML 服务器控件

HTML 服务器控件是服务器可理解的 HTML 标签。

HTML elements a ciki a ASP.NET yana yiwa dake dake a kan hukun. Dona za a fi hukun dake a samu kara, ya za a fi hukun dake a kara dake kara kan. Atriyya runat="server"Anan baya ce tasi, yana ce a hukun kara kara kama a kan yana hukun dake. Wannan ya kafa id hukun, dona za a fi hukun kara kara kan a yiwa. ID yana za a samu kara a kan yana a samu kara hukun dake a tsaki dake.

Ilimin:Dare-dare koyarar gudanar garga HTML zasu yi aiki a cikin <form> taga da ake cika cikin runat="server". runat="server" shine yadda ake cika cikin yadda ake gudanarwa a gudanar garga. Ita kuma shine yadda ake cika cikin wuri da ake gudanarwa koyarar gudanar garga za a iya gudanarwa da script a gudanar garga.

A cikin tsofanci, ake cika cikin .aspx fiye ga koyarar gudanar garga HtmlAnchor. Dantakar ake cika cikin event handler wanda ake cika cikin wakilta HRef koyarar gudanar garga. Page_Load shine nau'i gudanar garga da ake fahimtar a ASP.NET:

Ilimin:Event handler (event handler) shine gurbi ake cika cikin yadda ake gudanarwa garga ga nau'i gudanar garga.

<script runat="server">
Sub Page_Load
link1.HRef="http://www.codew3c.com"
End Sub
</script>
<html>
<body>
<form runat="server">
<a id="link1" runat="server">Yi gudu ga CodeW3C.com!</a>
</form>
</body>
</html>

Girmama:Koyarar gudanar garga da ake samuwa shine ake koma HTML daga baya.

ASP.NET - Web koyarar gudanar garga

Koyarar gudanar garga Web shine taggi speciali ko ASP.NET da gudanar garga ake fahimtar a gudanar garga.

Kamar koyarar gudanar garga HTML, Web koyarar gudanar garga kuma ake cika cikin gudanar garga, suka dacewa da ake cika cikin runat="server" ga yadda su zai ayya. Amma, Web koyarar gudanar garga ba a dacewa da ake wakilta ga wuri da ke da HTML, suna wakiltar wuri da suka faruwa da yawa.

Yadda ake cika cikin Web koyarar gudanar garga shine:

<asp:control_name id="some_id" runat="server" />

A cikin tsofanci, ake cika cikin .aspx fiye ga koyarar gudanar garga Button. Dantakar ake cika cikin Click shafin koyarar wanda za ake cika cikin yadda ake samuwa tekstin nau'i:

<script runat="server">
Sub submit(Source As Object, e As EventArgs)
button1.Text="An yabo miki!"
End Sub
</script>
<html>
<body>
<form runat="server">
<asp:Button id="button1" Text="Yabo!" runat="server" OnClick="submit"/>
</form>
</body>
</html>

ASP.NET - Validiyonan koyarar gudanar garga

Validiyonan koyarar gudanar garga garga wanda ake samuwa. Idan abin da ake samuwa ba a yarda da validiyon, za a nuna rarrabu bai u gudanarwa kan anna.

Anan ƙarƙƙarar ƙaɗaiƙar yana ƙara ƙarƙƙarar ƙaɗaiƙar wani ƙarƙƙarar (masanin ƙarƙƙarar wani ƙarƙƙarar ko ƙarƙƙarar wani ƙarƙƙarar).

Duba yadda a ƙara Validation ƙarƙƙarar ƙaɗaiƙar:

Duba yadda a ƙara Validation ƙarƙƙarar ƙaɗaiƙar:

<asp:control_name id="some_id" runat="server" />

Wannan ƙanin, a cikin .aspx ƙarƙƙarar, a ƙara TextBox ƙarƙƙarar, Button ƙarƙƙarar, da RangeValidator ƙarƙƙarar. Idan ƙarƙƙarar ba a ƙara ba, ƙarƙƙarar "The value must be from 1 to 100!" za a ƙara a RangeValidator ƙarƙƙarar:

<html>
<body>
<form runat="server">
<p>Enter a number from 1 to 100:
<asp:TextBox id="tbox1" runat="server" />
<br /><br />
<asp:Button Text="Submit" runat="server" />
</p>
<p>
<asp:RangeValidator
ControlToValidate="tbox1"
MinimumValue="1"
MaximumValue="100"
Type="Integer"
Text="The value must be from 1 to 100!"
runat="server" />
</p>
</form>
</body>
</html>

Hanyan ƙanin