更新需要在程序后端里边完成如:
自增方法:db('数据表名')->where('条件')->setInc('字段',值);
例子:db('team')->where('teamid',$teamid)->setInc('score',3);//球队积分加3
自减方法:db('数据表名')->where('条件')->setDec('字段',值);
例子:db('team')->where('teamid',$teamid)->setDec('score',3);//球队积分减3
下面是实现的代码: DataTable table = new DataTable();//初始化一个DataTable对象 string sqlConnectionString = "Data Source=ComputerName-PC;Initial Catalog=charge_sys;User ID=sa;PWD=123456;"; SqlConnection sqlConnection = new SqlConnection(sqlConnectionString);//连接数据库 SqlCommand sqlCommand = new SqlCommand("select from testB", sqlConnection); SqlDataAdapter sqlAdap = new SqlDataAdapter(sqlCommand); SqlCommandBuilder sqlBuilder = new SqlCommandBuilder(sqlAdap);//这句挺重要的,好像是批量更新的时候用 //DataSet dtst = new DataSet(); 用dataSet也可以完成,下面有对应实现的代码 sqlConnectionOpen(); sqlAdapFill(table); //table = dtstTables["testB"]; DataRow dr = tableRows[0];//第一行 //drBeginEdit(); //drEndEdit(); 貌似这两句主要是数据绑定到控件的时候才用 for (int i = 0; i < tableRowsCount; i++) //修改table中每一行的内容 { dr = tableRows[i]; dr["f"] = 3; //字段名为f } //testB表中必须存在主键,否则无法更新// 这个很重要 sqlAdapUpdate(table); //sqlAdapUpdate(dtst, "testB"); sqlConnectionClose(); MessageBoxShow("aa"); 下面是DataTable与dataGridView 控件绑定,当dataGridView中的数据改变时,更新数据库的代码: DataTable和dataGridView控件绑定代码:private void Form1_Load(object sender, EventArgs e) { string sqlConnectionString = "Data Source=ComputerName-PC;Initial Catalog=charge_sys;User ID=sa;PWD=123456;"; SqlConnection sqlConnection = new SqlConnection(sqlConnectionString);//初始化sqlconnection DataTable table = new DataTable(); SqlDataAdapter sqlAdap = new SqlDataAdapter("select from testB ", sqlConnection); sqlConnectionOpen(); sqlAdapFill(table); sqlConnectionClose(); //将testB表中的数据显示在dataGridView中 thisdataGridView1DataSource = table; } 实现将dataGridView中的改动更新到数据库代码:private void butUpdate_Click(object sender, EventArgs e) { DataTable table = new DataTable(); table = (DataTable)thisdataGridView1DataSource; string sqlConnectionString = "Data Source=WangHaitao-PC;Initial Catalog=charge_sys;User ID=sa;PWD=123456;"; SqlConnection sqlConnection = new SqlConnection(sqlConnectionString); SqlCommand sqlCommand = new SqlCommand("select from testB", sqlConnection); SqlDataAdapter sqlAdap = new SqlDataAdapter(sqlCommand); SqlCommandBuilder sqlBuilder = new SqlCommandBuilder(sqlAdap);//必须有 sqlConnectionOpen(); sqlAdapFill(table); //testB表中必须存在主键,否则无法更新 sqlAdapUpdate(table); sqlConnectionClose(); MessageBoxShow("aa"); }
1、设置一个DB_VERSION
public static final int DB_VERSION = 1;2、当你要更新表的时候就把DB_VERSION+1,就会触发onUpgrade,数据库就更新了,记得采纳
public DBHelper() {// for test
daoConfig = new DbManagerDaoConfig()
setDbName(DB_NAME)
setDbVersion(DB_VERSION)
setDbDir(EnvironmentgetExternalStorageDirectory())
setDbOpenListener(new DbManagerDbOpenListener() {
@Override
public void onDbOpened(DbManager db) {
dbgetDatabase()enableWriteAheadLogging();
}
})
setDbUpgradeListener(new DbManagerDbUpgradeListener() {
@Override
public void onUpgrade(DbManager db, int oldVersion, int newVersion) {
updateTable(db, xxclass);
}
});
}
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