Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
404 views
in Technique[技术] by (71.8m points)

.net - Reading values from SQL database in C#

i have just started learning C# and i can write data to the database without a problem. But i'm having problems with reading, the SQL executes fine but i'm having issues with storing it. How would i store the four columns that should be returned and then show them as a message box? Thanks.

SqlCommand myCommand = new SqlCommand("select * from Requests where Complete = 0", myConnection);
SqlDataReader myReader = myCommand.ExecuteReader();
while (myReader.Read())

Console.WriteLine(myReader["Username"].ToString());
Console.WriteLine(myReader["Item"].ToString());
Console.WriteLine(myReader["Amount"].ToString());
Console.WriteLine(myReader["Complete"].ToString());
See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Reply

0 votes
by (71.8m points)

One problem is missing braces after the while

while (myReader.Read())
{  // <<- here
    Console.WriteLine(myReader["Username"].ToString());
    Console.WriteLine(myReader["Item"].ToString());
    Console.WriteLine(myReader["Amount"].ToString());
    Console.WriteLine(myReader["Complete"].ToString());
}  // <<- here

if you skip the braces only the first line will be processed in each loop, the rest will be processed after the loop, then myReader is past the last row.


与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
OGeek|极客中国-欢迎来到极客的世界,一个免费开放的程序员编程交流平台!开放,进步,分享!让技术改变生活,让极客改变未来! Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...