将Datareader转换为字符串 [英] Convert Datareader to String

问题描述

我需要将sqlDataReader转换为String，以便将数据库值与用户输入的文本值进行比较

i need to convert the sqlDataReader to String for the comparing of database value to user entered text value
how to do?

推荐答案

如db7uk的注释中所述，您不能将数据读取器转换为字符串.您可以做的是使用数据读取器提取值.

此处 [

As mentioned in the comments by db7uk, you can''t convert a datareader into a string. What you CAN do is to use the datareader to pull values.

Here[^] is an article that I found on google that may help you.

sqlconnection con = new sql connction("connection string");
sqlcommand com = new sqlcommand("select columnname from  tablename",con);
con.open();
sqldatareader dr = com.excutereader();
dr.read();

if(!dr.IsDBNull(0) && textbox1.text==dr.GetString(0))
{
    messagebox.show("anything");
}

con.close();

希望这对您有帮助

hope this helps

在这种情况下可以使用

if(dr ["City"]！= null)
{
objAdsProperties.City = dr ["City"]作为字符串；
}
其他
{
objAdsProperties.City =";
}


对于整数值

objAdsProperties.BuiltYear = dr ["BuiltYear"]为int吗? ?? default(int);

this will work in this case

if (dr["City"] != null)
{
objAdsProperties.City = dr["City"] as string;
}
else
{
objAdsProperties.City = "";
}


for integer value

objAdsProperties.BuiltYear = dr["BuiltYear"] as int? ?? default(int);

这篇关于将Datareader转换为字符串的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！