示例errchecktest
為容易出錯的**段加上trycatch (exception ex) 防止崩潰。
建立vs2015 c#專案：errchecktest
insertdatatest模板
修改**
程式執行時，在按扭上胡亂點，哪個語句有問題，就用下面的格式：
try有問題的**
catch(exception ex)
messagebox.show(ex.message);
//或者輸出自己確定的出問題原因
完整**
using system;
using system.data;
using system.windows.forms;
using system.io;
using firebirdsql.data.firebirdclient;
namespace errchecktest
publicpartialclassfrmmain : form
public frmmain()
initializecomponent();
publicfbconnection myconnection;
staticstringgetconnectionstring()// 連線字串
fbconnectionstringbuilder cs = newfbconnectionstringbuilder();
cs.userid = "sysdba";
cs.password = "masterkey";
cs.database = application.startuppath + "\\data\\測試.fdb";
cs.datasource = "localhost";
cs.charset = "utf8";
cs.port = 3050;
cs.dialect = 3;
cs.role = "";
cs.connectionlifetime = 15;
cs.pooling = true;
cs.minpoolsize = 0;
cs.maxpoolsize = 50;
cs.packetsize = 8192;
cs.servertype = fbservertype.embedded;
return cs.tostring();
privatevoid btncreatedb_click(object sender, eventargs e)
//建立資料庫
string path = application.startuppath + "\\data\\測試.fdb";
tryif (file.exists(path))
file.delete(path);
fbconnection.createdatabase(getconnectionstring());
messagebox.show("檔案存在，刪除重建!");
else
fbconnection.createdatabase(getconnectionstring());
messagebox.show("檔案不存在，直接建立!");
catch (exception ex)
messagebox.show(ex.message);
privatevoidbtnopendb_click(object sender, eventargs e)
//開啟資料庫
myconnection = newfbconnection(getconnectionstring());
trymyconnection.open();
messagebox.show("開啟連線成功!");
catch (exception ex)
messagebox.show(ex.message);
privatevoidbtncreatetable_click(object sender, eventargs e)
//建立空表
tryfbcommand createtable = myconnection.createcommand();
createtable.commandtext = "create table testtbl (id int,\"姓名\" varchar(20))";
createtable.executenonquery();
createtable.dispose();
messagebox.show("建立空表成功!");
catch (exception ex)
messagebox.show(ex.message);
privatevoidbtnbindd**iew_click(object sender, eventargs e)
//datagridview顯示資料
fbdataadapter dt = newfbdataadapter("select * from testtbl", myconnection);
dataset ds = newdataset();
trydt.fill(ds, "testtbl");
this.d**iewdb.datasource = ds;
this.d**iewdb.datamember = "testtbl";
messagebox.show("datagridview顯示資料!");
catch (exception ex)
messagebox.show(ex.message);
dt.dispose();
ds.dispose();
privatevoidbtninsertdata_click(object sender, eventargs e)
//插入資料
try//插入資料一
fbcommand insertdata = myconnection.createcommand();
insertdata.commandtext = "insert into testtbl values(@id, @name)";
insertdata.parameters.clear();
insertdata.parameters.add("@id", fbdbtype.integer).value = 1;
insertdata.parameters.add("@name", fbdbtype.varchar, 20).value = "張三";
insertdata.executenonquery();
//插入資料二
insertdata.commandtext = "insert into testtbl values(@id, @胡作非為)";
insertdata.parameters.clear();
insertdata.parameters.add("@id", fbdbtype.integer).value = 2;
insertdata.parameters.add("@胡作非為", fbdbtype.varchar, 20).value = "李四";
insertdata.executenonquery();
insertdata.dispose();
messagebox.show("插入資料成功!");
catch (exception ex)
messagebox.show(ex.message);
privatevoidbtnreaddata_click(object sender, eventargs e)
//讀取資料
tryfbcommand readdata = myconnection.createcommand();
readdata.commandtext = "select * from testtbl";
fbdatareader reader = readdata.executereader();
while (reader.read())
string str_temp = reader.getstring(0);
messagebox.show(str_temp);
str_temp =reader.getstring(1);
messagebox.show(str_temp);
readdata.dispose();
messagebox.show("讀取資料成功!");
catch (exception ex)
messagebox.show(ex.message);
privatevoidbtnconnectionclose_click(object sender, eventargs e)
//關閉連線
trymyconnection.close();
messagebox.show("連線已關閉!");
catch (exception ex)
messagebox.show(ex.message);
測試成功
但下面問題未解決：只要開啟一次資料庫，無論關不關閉連線，都會出現?誰能給出個原因啊!
嵌入式firebird VS2015例項十三
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