C#查询语句

发布网友 发布时间：2022-04-19 13:01

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热心网友 时间：2023-08-31 03:56

//控件够了已不用再拉
string str="server=localhost;uid=sa;pwd=sa;database=mysql";
string source="select * from Book where BookID="+this.textBox1.Text;
SqlConnection conn=new SqlConnection(str);
SqlDataAdapter sqlDataAdapter1=new SqlDataAdapter(conn,sourec);//实例化一个DataAdapter
DataSet objDataSet1=new DataSet();//实例化一个DataSet
sqlDataAdapter1.Fill(objDataSet1,"Book");//把符合条件的数据填充到DataSet.
if(objDataSet1.Table["Book"].Rew.Count!=0)//判断DataSet里有无记录
this.dataGrid1.DataSource=objDataSet1.Table["Book"];
else
MessageBox.Show("输入有误");
//要记得using Syatem.Data.SqlClient;sqlDataAdapter1和objDataSet1可以在类一级下声明

热心网友 时间：2023-08-31 03:57

//鎺т欢澶熶简宸蹭笉鐢ㄥ啀鎷�
string str="server=localhost;uid=sa;pwd=sa;database=mysql";
string source="select * from Book where BookID="+this.textBox1.Text;
SqlConnection conn=new SqlConnection(str);
SqlDataAdapter sqlDataAdapter1=new SqlDataAdapter(conn,sourec);//瀹炰緥鍖栦竴涓狣ataAdapter
DataSet objDataSet1=new DataSet();//瀹炰緥鍖栦竴涓狣ataSet
sqlDataAdapter1.Fill(objDataSet1,"Book");//鎶婄�鍚堟浔浠剁殑鏁版嵁濉�厖鍒瘅ataSet.
if(objDataSet1.Table["Book"].Rew.Count!=0)//鍒ゆ柇DataSet阅屾湁镞犺�褰�
this.dataGrid1.DataSource=objDataSet1.Table["Book"];
else
MessageBox.Show("杈揿叆链夎�");

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SqlDataAdapter sqlDataAdapter1=new SqlDataAdapter(conn,sourec);//瀹炰緥鍖栦竴涓狣ataAdapter
鍦ㄨ繖琛屼腑鎴戣�涓烘槸SqlDataAdapter sqlDataAdapter1=new SqlDataAdapter(sourec,conn);//瀹炰緥鍖栦竴涓狣ataAdapter