C# Signature:

[DllImport("odbccp32.dll", SetLastError=true)]
static extern bool SQLSetConfigMode(ConfigMode configMode);

VB Signature:

Declare Function SQLSetConfigMode Lib "odbccp32.dll" (TODO) As TODO

User-Defined Types:

enum ConfigMode

{

    ODBC_BOTH_DSN = 0,
    ODBC_USER_DSN = 1,
    ODBC_SYSTEM_DSN = 2,

}

Sample Code:

This function persists a system data source with the provided name and connection string. Remember to add your own error checking mechanisms.

void UpdateDSN(string dataSourceName, string connStr)

{

    char[] value = new char[8192];

    // Try to retrieve the driver for the data source
    SQLSetConfigMode(ConfigMode.ODBC_SYSTEM_DSN);
    SQLGetPrivateProfileString(dataSourceName, "Driver", "", value, value.Length, "odbc.ini");

    // Set our configuration mode
    RequestFlags configMode = value[0] == '\0' ? RequestFlags.ODBC_ADD_SYS_DSN : RequestFlags.ODBC_CONFIG_SYS_DSN;

    // Connection string for SQLConfigDataSource must be null-
    // character delimited and double null-terminated
    string s = connStr.Replace(';', '\0');
    s += '\0';

    // Persist the data source
    SQLConfigDataSourceW(0, configMode, MY_DRIVER_NAME_STRING, s);

}