ASP. Dynamically modify the setting items in web.config (background CS code) in web.config (background CS code)

Friends can test it by myself. I have no problem here. I finally solved the problems in the morning.

using system;

using system.collections;

using system.componentmodel;

using system.data;

using system.drawing;

using system.web;

using system.web.sessionState;

using system.web.ui;

using system.web.ui.webcontrols;

using system.web.ui.htmlControls;

using system.xml;

namespace webapplication1

{{

/// <summary>

/// Summary description for webform1.

/// </summary>

public class webform1: system.web.ui.page

{{

Protected system.web.ui.webcontrols.textbox textbox1;

Protected system.web.ui.webcontrols.dropdownList DropdownList1;

Protected system.web.ui.webcontrols.button Button1;

public webform1 ()

{{

pay.init += new system.eventhandler (page_init);

}

Private void page_load (Object Sender, System.eventargs E)

{{

if (! Page.ispostback)

{{

// Open a file (assume that web.config is in the root directory)

string filename = server.mappath (/) + @/web.config;

xmldocumentxmldoc = new xmldocument ();

xmldoc.load (FILENAME);

XMLNODELIST TOPM = xmldoc.documentedLement.childNodes;

Foreach (Xmlelement Element in Topm)

{{

if (Element.name.tology () == AppSettings))

{{

XMLNODELIST_NODE = ELEMENT.CHILDNODES;

if (_Node.count> 0)

{{

DropdownList1.Items.clear ();

Foreach (xmlelement el in _Node)

{{

DropdownList1.Items.add (El.attributes [Key] .innerxml);

}

}

}

}

}

}

Private void page_init (Object Sender, EventArgs E)

{{

initializeComponent ();

}

#Region web form designer generated code

/// <summary>

/// Required Method for Designer Support -Do Not Modify

/// the contents of this method with the code editor.

/// </summary>

Private void InitializeComponent ()

{{

this.Button1.clICK += New System.eventhandler (this.Button1_Click);

this.load += new system.eventhandler (this.page_load);

}

#Endregion

Private void button1_click (Object Sender, System.eventargs E)

{{

string filename = server.mappath (/) + @/web.config;

xmldocumentxmldoc = new xmldocument ();

xmldoc.load (filename);

XMLNODELIST TOPM = xmldoc.documentedLement.childNodes;

Foreach (Xmlelement Element in Topm)

{{

if (Element.name.tology () == AppSettings))

{{

XMLNODELIST_NODE = ELEMENT.CHILDNODES;

if (_Node.count> 0)

{{

Foreach (xmlelement el in _Node)

{{

If (El.attributes [Key] .innerxml.tology () == this.dropdownlist1.selectEdItem.Value.tolower ())

{{

el.attributes [value]. Value = this.textbox1.text;

}

}

}

}

}

xmldoc.save (filename);

}

}

}