c# - 'SqlConnection' does not contain a constructor that takes 4 arguments -


this code:

public void sqldbconnect() {     sqlconnection conn = new sqlconnection("data source={0};user id={1};password={2};", server, user, password);     conn.open(); }

i try make connection via server name, user , pass.

you need format string , pass string constructor (this c# 6 specific feature):

sqlconnection conn = new sqlconnection($"data source={server};user id={user};password={password};");

or in older c# versions can use string.format:

sqlconnection conn = new sqlconnection(string.format("data source={0};user id={1};password={2};", server, user, password));

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