点，逗号等转换成特殊符号“？”在iphone中

Question

我正在使用数据库来获取数据。数据库中有近750个问题。一些问题包含特殊字符，如“，......，”等，但在获取数据并在文本视图中打印时，它会转换为“？”。有没有办法删除这些一种符号并以原始格式打印。

我使用以下代码在textview中获取和显示。

    qsql=[NSString stringWithFormat:@"Select * from mydata where col_1 = '365'"];

    if(sqlite3_prepare_v2(database, [qsql UTF8String], -1, &statement, NULL) == SQLITE_OK) {
        while (sqlite3_step(statement) == (SQLITE_ROW))
    { 

        char *field0 = (char *)sqlite3_column_text(statement, 1);
        char *field1 = (char *)sqlite3_column_text(statement, 2);
        NSString *t1 = nil;
        if(field0!=NULL){
          t1 = [[NSString alloc] initWithUTF8String:field0];
            //NSString *t1 = [[NSString alloc] initWithCString:field0 encoding:NSUTF8StringEncoding];
            NSLog(@"%@jujuj" ,t1);
        }
        NSString *t2 = nil;
        if(field1!=NULL){
            t2 = [[NSString alloc] initWithUTF8String:field1];
             NSLog(@"%@jhjhh" ,t2);
        }


        NSString *string=t1;
        NSCharacterSet *doNotWant = [NSCharacterSet characterSetWithCharactersInString:@",."];
      string = [[string componentsSeparatedByCharactersInSet:doNotWant] componentsJoinedByString:@""];
        NSLog(@"%@jhgkjghkjg",string);
        //NSLog(@"%@ %@",Q_NO, Q_NO1);
        tv.text=t1;
        tv1.text=t2;



        [t1 release];
        [t2 release];
    }  
}

Answer 1

使用NSCharacterSet从字符串中删除该特殊字符

NSString *string = @"ram,...";
    NSCharacterSet *doNotWant = [NSCharacterSet characterSetWithCharactersInString:@",."];
    string = [[string componentsSeparatedByCharactersInSet:doNotWant] componentsJoinedByString:@""];
    NSLog(@"%@",string);

Answer 2

像这样使用

    const char *sqlStatement = Select * from mydata where col_1 = '365'"; 
sqlite3_stmt *compiledStatement; 


if(sqlite3_prepare_v2(database, sqlStatement, -1, &compiledStatement, NULL) == SQLITE_OK) 
    {

        while (sqlite3_step(compiledStatement) == SQLITE_ROW)
        {

            nsstring *t1 = [NSString stringWithFormat:@"%s",(char*)sqlite3_column_text(compiledStatement, 1)];