20131207-ado. net-16th Day

[1] Shortcut keys

Toolbox: ctrl+w+x initial position Control range

Properties: F4 or Ctrl+w+p tab jump, home and end also valid

[2] Connection string

String str = "Data source=xy-pc;initial catalog=myitcast;integrated security=true";

[*]

[3]

Using System;

Using System.Collections.Generic;

Using System.ComponentModel;

Using System.Data;

Using System.Drawing;

Using System.Linq;

Using System.Text;

Using System.Windows.Forms;

Using System.Data.SqlClient;

Namespace _06 Major Project

{

public partial class Form1:form

{

Public Form1 ()

{

InitializeComponent ();

}

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private void btnAdd_Click (object sender, EventArgs e)

{

Get the contents of the text box--to judge (you do)

String name = txtaddname.text;//Name

int gender = Txtaddgender.text = = "Male"? 1:txtaddgender.text = = "female"? 0:2;//standing buried-pit//Tai Hang

Judge whether the value of the sex is 1 or 0 if not, tell the user to enter the error please re-enter (left you)

int ages = Convert.ToInt32 (txtaddage.text);//Age--pit (left for you)

string phone = txtaddphone.text;//phone number

Create a connection string

String str = "Data source=xy-pc;initial catalog=myitcast;integrated security=true";

int count =-1;

Connecting to a database

using (SqlConnection con = new SqlConnection (str))

{

String sql = string. Format ("INSERT into Tblstudent (TSNAME,TSGENDER,TSAGE,TSPHONE,TCLASSID) VALUES (' {0} ', {1},{2}, ' {3} ', {4})", Name, Gender, age, phone, 1);

using (SqlCommand cmd = new SqlCommand (sql, con))

{

Open Database

Con. Open ();

Count = cmd. ExecuteNonQuery ();//Execute SQL statement

}

}

Execute SQL statement

if (Count > 0)

{

MessageBox.Show ("add success");

}

Else

{

MessageBox.Show ("Add failed");

}

Results

}

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private void Form1_Load (object sender, EventArgs e)

{

Loadallstudent ();//Load Students

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}

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private void Loadallstudent ()

{

Create a collection that stores each student object

list<student> list = new list<student> ();

Encapsulation into a method---to refresh it.

Querying all the data

String str = "Data source=xy-pc;initial catalog=myitcast;integrated security=true";//Create connection string

Connecting to a database

using (SqlConnection con = new SqlConnection (str))

{

String sql = "Select Tsid, Tsname,tsgender,tsage,tsphone from Tblstudent";

using (SqlCommand cmd = new SqlCommand (sql, con))

{

Con. Open ();//Opening the database

using (SqlDataReader SDA = cmd. ExecuteReader ())

{

if (SDA. HasRows)//If True proves that there is at least one piece of data

{

while (SDA. Read ())//reads to the next bar

{

sda[1]//data for each column

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Student stu = new Student ();//Create a Student object

Stu. TSId = SDA. GetInt32 (0);//value of primary key ID

Stu. Tsname = sda["Tsname"]. ToString ();

Stu. Tsgender = SDA. Getboolean (2) = = true? ' Male ': ' Female ';

Stu. Tsage = SDA. GetInt32 (3);//Age

Stu. Tsphone = SDA. GetString (4);

List. ADD (Stu);

}

}

}

}

}

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DGV. DataSource = list;//binds the collection to the control

}

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private void Deletetsm_click (object sender, EventArgs e)

{

First, determine whether the user selected the row

if (DGV. Selectedrows.count > 0)

{

int count=-1;

String id = DGV. Selectedrows[0]. Cells[0]. Value.tostring ();

Create a connection string

String str = "Data source=xy-pc;initial catalog=myitcast;integrated security=true";

Connecting to a database

using (SqlConnection con=new SqlConnection (str))

{

String sql = "Delete from tblstudent where tsid=" +ID;

using (SqlCommand cmd=new SqlCommand (Sql,con))

{

Con. Open ();

Count =cmd. ExecuteNonQuery ();

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}//End Using

}//end using

if (count>0)

{

Loadallstudent ();

MessageBox.Show ("delete succeeded");

}

Else

{

MessageBox.Show ("delete failed");

}

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}//end if

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Gets the ID of the selected row

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MessageBox.Show ("deleted");

}

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private void Dgv_rowenter (object sender, DataGridViewCellEventArgs e)

{

Whether there is a selected row

if (DGV. SELECTEDROWS.COUNT>0)

{

Get ID Name Gender age

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Labid.text = DGV. Selectedrows[0]. Cells[0]. Value.tostring (); Value of//id

Name

Txtupname.text = DGV. Selectedrows[0]. CELLS[1]. Value.tostring ();

Gender

Txtupgender.text = DGV. Selectedrows[0]. CELLS[2]. Value.tostring ();

Age

Txtupphone.text = DGV. Selectedrows[0]. CELLS[3]. Value.tostring ();

Txtupage.text = DGV. Selectedrows[0]. CELLS[4]. Value.tostring ();

}

}

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private void Btnupdate_click (object sender, EventArgs e)

{

int count =-1;

First gets the ID of the currently selected row

string id = labid.text;

int gender = Txtupgender.text = = "Male"? 1:txtupgender.text = = "female"? 0:2;

int gender = Txtupgender.text = = "Male"? 1:0;

Create a string to connect to the database

String str = "Data source=xy-pc;initial catalog=myitcast;integrated security=true";

Connecting to a database

using (SqlConnection con=new SqlConnection (str))

{

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String sql =string. Format ("Update tblstudent set Tsname= ' {0} ', tsgender={1},tsage={2},tsphone= ' {3} ' where Tsid={4} ', Txtupname.text, GENDER,TXTUPAGE.TEXT,TXTUPPHONE.TEXT,ID);

using (SqlCommand cmd=new SqlCommand (Sql,con))

{

Con. Open (); Open Database

count= cmd. ExecuteNonQuery ();

}

}

if (count>0)

{

Loadallstudent ();//Refresh

MessageBox.Show ("modified successfully");

}

Else

{

MessageBox.Show ("modification failed");

}

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Perform

}

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private void Btncount_click (object sender, EventArgs e)

{

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String count = "";

Create a connection string

String str = "Data source=xy-pc;initial catalog=myitcast;integrated security=true";

Connecting to a database

using (SqlConnection con=new SqlConnection (str))

{

String sql = "SELECT COUNT (*) from tblstudent";

using (SqlCommand cmd=new SqlCommand (Sql,con))

{

Con. Open ();//Opening the database

count= cmd. ExecuteScalar (). ToString ();

}

}

Open Database

MessageBox.Show ("A total of" +count+ "Children's Shoes");

Execute SQL statement

}

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}

}

Data to Object

Using System;

Using System.Collections.Generic;

Using System.Linq;

Using System.Text;

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Namespace _06 Major Project

{

public class Student

{

TSId, Tsname, Tsgender, tsaddress, Tsphone, Tsage, Tsbirthday, Tscardid, Tclassid

Which column to write in

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Query four columns

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private int _tsid;

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public int TSId

{

get {return _tsid;}

set {_tsid = value;}

}

private string _tsname;

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public string Tsname

{

get {return _tsname;}

set {_tsname = value;}

}

Private char _tsgender; Keng

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Public Char Tsgender

{

get {return _tsgender;}

set {_tsgender = value;}

}

private string _tsphone;

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public string Tsphone

{

get {return _tsphone;}

set {_tsphone = value;}

}

private int _tsage;

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public int Tsage

{

get {return _tsage;}

set {_tsage = value;}

}

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}

}

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20131207-ado. net-16th Day