Question

我正在尝试使用HTTP请求ping eBay的API，但是Xcode给了我错误No known class method for selector stringWithFormat。我想在这里做的是将searchField中输入的任何字符串追加到url的末尾。我究竟做错了什么？感谢任何帮助！

- (void) prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{

    if (sender != self.nextButton) return;
    if (self.searchField.text.length > 0) {
        self.responseData = [NSMutableData data];
        NSURLRequest *request = [NSURLRequest requestWithURL:
                                 [NSURL stringWithFormat:@"http://svcs.ebay.com/services/search/FindingService/v1?SECURITY-APPNAME=***APP ID ****&OPERATION-NAME=findItemsByKeywords&SERVICE-VERSION=1.12.0&RESPONSE-DATA-FORMAT=JSON&callback=_cb_findItemsByKeywords&REST-PAYLOAD&sortOrder=PricePlusShippingLowest&paginationInput.entriesPerPage=3&itemFilter(2).paramName=Currency&itemFilter(2).paramValue=USD&itemFilter(3).name=ListingType&itemFilter(3).value=FixedPrice&keywords=%@", self.searchField.text]];


        [[NSURLConnection alloc] initWithRequest:request delegate:self];
    }

}

Answer 1

您首先需要创建一个包含该网址的NSString，然后在其中创建一个NSURL。

NSString *urlString = [NSString stringWithFormat:@"http://example.com/",
    self.searchField.text];
NSURL *url = [NSURL URLWithString:urlString];

Answer 2

    NSURLRequest *req = [NSURLRequest requestWithURL:[NSURL URLWithString:[NSString stringWithFormat:@"http://svcs.ebay.com/services/search/FindingService/v1?SECURITY-APPNAME=***APP ID ****&OPERATION-NAME=findItemsByKeywords&SERVICE-VERSION=1.12.0&RESPONSE-DATA-FORMAT=JSON&callback=_cb_findItemsByKeywords&REST-PAYLOAD&sortOrder=PricePlusShippingLowest&paginationInput.entriesPerPage=3&itemFilter(2).paramName=Currency&itemFilter(2).paramValue=USD&itemFilter(3).name=ListingType&itemFilter(3).value=FixedPrice&keywords=%@", self.searchField.text]]];

你错过了一个步骤，NSURL没有一个名为stringWithFormat的方法。

ping API时stringWithFormat错误

2 个答案: