Common skills for Asp.net Development

1.Open a new window and send parameters:

Transfer Parameters:

Response. Write ("<SCRIPT> window. Open ('*. aspx? Id = "+ this. dropdownlist1.selectindex +" & id1 = "++" ') </SCRIPT> ")

Receiving parameters:

String A = request. querystring ("ID ");

String B = request. querystring ("id1 ");

Comments: This method is suitable for the loose coupling of page layout. However, if your page has strict layout requirements, it may be misplaced during actual execution because after executing this code, scripts are generated on the page. These scripts are displayed in the browser, which leads to the number of the page layout. A simple solution is to use the registerclientscriptblock method.

 

 

2.Add button dialog box

Button1.attributes. Add ("onclick", "Return confirm ('OK? ')");

Button. Attributes. Add ("onclick", "If (confirm ('Are you sure? ') {Return true;} else {return false ;}")

Comments: for ASP. net2.0, you can also use the onclientclick event.

 

3.Delete selected table records

Int intempid = (INT) mydatagrid. datakeys [E. Item. itemindex];

String deletecmd = "delete from employee where emp_id =" + intempid. tostring ()

4.Delete table record warning

Private void datagrid_itemcreated (Object sender, datagriditemeventargs E)

{

Switch (E. Item. itemtype)

{

Case listitemtype. item:

Case listitemtype. alternatingitem:

Case listitemtype. edititem:

Tablecell mytablecell;

Mytablecell = E. Item. cells [14];

Linkbutton mydeletebutton;

Mydeletebutton = (linkbutton) mytablecell. controls [0];

Mydeletebutton. Attributes. Add

("Onclick", "Return confirm ('Are you sure you want to delete this information ');");

Break;

Default:

Break;

}

}

Comment: This is essentially the same as the technique described above.

 

5.Click the table row link to another page.

Private void grdcustomer_itemdatabound

(Object sender, system. Web. UI. webcontrols. datagriditemeventargs E)

{

// Click Open Table

If (E. Item. itemtype = listitemtype. Item |

E. Item. itemtype = listitemtype. alternatingitem)

E. Item. Attributes. Add ("onclick", "window. Open

('Default. aspx? Id = "+ E. Item. cells [0]. Text + "');");

}

Double-click a table to connect to another page. In the itemdatabind event

If (E. Item. itemtype = listitemtype. Item |

E. Item. itemtype = listitemtype. alternatingitem)

{

String orderitemid = E. Item. cells [1]. text;

E. Item. Attributes. Add ("ondblclick", "location. href = '.../shippedgrid. aspx? Id = "+ orderitemid + "'");

}

Double-click a table to open a new page.

If (E. Item. itemtype = listitemtype. Item |

E. Item. itemtype = listitemtype. alternatingitem)

{

String orderitemid = E. Item. cells [1]. text;

E. Item. Attributes. Add ("ondblclick ",

"Open ('../shippedgrid. aspx? Id = "+ orderitemid + "')");

}

★Note :【? Id =] cannot be 【? Id =]

 

6.Parameters for table hyperjoin Columns

<Asp: hyperlinkcolumn target = "_ blank" headertext = "ID" datatextfield = "ID"

Navigateurl = "AAA. aspx? Id = '<% # databinder. eval (container. dataitem, "data field 1") %>'

& Name = '<% # databinder. eval (container. dataitem, "data field 2") %>'/>

7.Change table color

If (E. Item. itemtype = listitemtype. Item | E. Item. itemtype = listitemtype. alternatingitem)

{

E. Item. Attributes. Add ("onclick", "This. style. backgroundcolor = '#99cc00 ';

This. style. Color = 'buttontext'; this. style. cursor = 'default ';");

}

Written in _ itemdatabound of the DataGrid

If (E. Item. itemtype = listitemtype. Item | E. Item. itemtype = listitemtype. alternatingitem)

{

E. Item. Attributes. Add ("onmouseover", "This. style. backgroundcolor = '#99cc00 ';

This. style. Color = 'buttontext'; this. style. cursor = 'default ';");

E. Item. Attributes. Add ("onmouseout", "This. style. backgroundcolor =''; this. style. Color = '';");

}

8.About Date Format

Date Format setting

Dataformatstring = "{0: yyyy-mm-dd}", in the itembound event

E. items. cell ["your column"]. TEXT = datetime. parse (E. items. cell ["your column"]. text. tostring ("yyyy-mm-dd "))

9.Get error information and go to the specified page

Instead of using response. Redirect, you should use server. Transfer

E. g

// In Global. asax

Protected void application_error (Object sender, eventargs e ){

If (server. getlasterror () is httpunhandledexception)

Server. Transfer ("myerrorpage. aspx ");

// Other non-httpunhandledexception exceptions are handed over to ASP. NET for processing and okay.

}

Redirect will lead to post-back loss of error information, so the page orientation should be executed directly on the server side, so that the error information can be obtained on the error handling page and processed accordingly

10.ClearCookie

Cookie. expires = [datetime];

Response. Cookies ("username"). expires = 0

 

11.Custom Exception Handling

// Custom exception handling class

Using system;

Using system. diagnostics;

Namespace myappexception

{

/** // <Summary>

/// Application exception handling class inherited from the system exception class applicationexception.

/// Automatically record the exception content to the application logs of Windows NT/2000

/// </Summary>

Public class appexception: system. applicationexception

{

Public appexception ()

{

If (applicationconfiguration. eventlogenabled)

Logevent ("an unknown error occurs. ");

}

Public appexception (string message)

{

Logevent (Message );

}

Public appexception (string message, exception innerexception)

{

Logevent (Message );

If (innerexception! = NULL)

{

Logevent (innerexception. Message );

}

}