本文介绍了如何使用Objective-C与SQLite进行数据绑定的方法，详细解释了不同数据类型的处理方式，包括空值、二进制数据、日期、数值类型等。
if ((!obj) || ((NSNull *)obj == [NSNull null])) {
sqlite3_bind_null(pStmt, idx);
}
// FIXME - someday check the return codes on these binds.
else if ([obj isKindOfClass:[NSData class]]) {
const void *bytes = [obj bytes];
if (!bytes) {
// it's an empty NSData object, aka [NSData data].
// Don't pass a NULL pointer, or sqlite will bind a SQL null instead of a blob.
bytes = "";
}
sqlite3_bind_blob(pStmt, idx, bytes, (int)[obj length], SQLITE_STATIC);
}
else if ([obj isKindOfClass:[NSDate class]]) {
if (self.hasDateFormatter)
sqlite3_bind_text(pStmt, idx, [[self stringFromDate:obj] UTF8String], -1, SQLITE_STATIC);
else
sqlite3_bind_double(pStmt, idx, [obj timeIntervalSince1970]);
}
else if ([obj isKindOfClass:[NSNumber class]]) {
if (strcmp([obj objCType], @encode(BOOL)) == 0) {
sqlite3_bind_int(pStmt, idx, ([obj boolValue] ? 1 : 0));
}
else if (strcmp([obj objCType], @encode(int)) == 0) {
sqlite3_bind_int64(pStmt, idx, [obj longValue]);
}
else if (strcmp([obj objCType], @encode(long)) == 0) {
sqlite3_bind_int64(pStmt, idx, [obj longValue]);
}
else if (strcmp([obj objCType], @encode(long long)) == 0) {
sqlite3_bind_int64(pStmt, idx, [obj longLongValue]);
}
else if (strcmp([obj objCType], @encode(unsigned long long)) == 0) {
sqlite3_bind_int64(pStmt, idx, (longlong)[obj unsignedLongLongValue]);
}
else if (strcmp([obj objCType], @encode(float)) == 0) {
sqlite3_bind_double(pStmt, idx, [obj floatValue]);
}
else if (strcmp([obj objCType], @encode(double)) == 0) {
sqlite3_bind_double(pStmt, idx, [obj doubleValue]);
}
else {
sqlite3_bind_text(pStmt, idx, [[obj description] UTF8String], -1, SQLITE_STATIC);
}
}
else {
sqlite3_bind_text(pStmt, idx, [[obj description] UTF8String], -1, SQLITE_STATIC);
}
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