比较两个字符串在 javascript 中无法正常工作

Question

这是我的 Javascript 函数，我在其中比较两个字符串，一个值作为函数参数接收，另一个值从 json 获取，后者来自 Spring 响应。

但我很惊讶我无法用 === 和 == 比较两个字符串，我可以在调试器中看到这些值。

我正在从我的 HTML 代码中调用我的函数：

<textarea onblur="searchProduct(this.value)"></textarea >

Javascript:

function searchProduct(value)
{
    alert(value);
    for (i in allProducts) {
        console.log(allProducts[0].productName);
        var tempProductName=allProducts[i].productName;
            alert(tempProductName.toString() == value.toString());
        // checks product name is present or not
        if( tempProductName.toString() === value.toString()){
//          setting other values details of products
                    $('#description').val(allProducts[i].productDescription);
                    $('.cost').val(allProducts[i].unitPrice);
        }//if

        }
}//searchProduct

allProducts: 来自 spring

的回复

[{"productId":3,"sku":"QTY","vendorProductId":"v1","productName":"P1name","productDescription":"p1 desc","supplierId":"s1","categoryId":"c","quantityPerUnit":1.0,"unitPrice":760.0,"msrp":1.0,"availableSize":40.0,"availableColors":"black,blue","size":40.0,"color":"white","discount":0.0,"unitWeight":1.0,"unitsInStock":148.0,"unitsOnOrder":500.0,"reorderLevel":150.0,"productAvailable":"Y","discountAvailable":"N","currentOrder":0.0,"pictureURL":"Picture path","ranking":10,"note":"Sample Notes","smsNotification":"N","productExpiryDate":null,"productDeleted":null,"alertExpiryDate":null,"idsku":"IDSKU1"},{"productId":4,"sku":"QTY","vendorProductId":"v1","productName":"P2name","productDescription":"p1 desc","supplierId":"s1","categoryId":"c","quantityPerUnit":1.0,"unitPrice":1.0,"msrp":1.0,"availableSize":40.0,"availableColors":"black,blue","size":40.0,"color":"white","discount":0.0,"unitWeight":1.0,"unitsInStock":150.0,"unitsOnOrder":500.0,"reorderLevel":150.0,"productAvailable":"Y","discountAvailable":"N","currentOrder":0.0,"pictureURL":"Picture path","ranking":10,"note":"Sample Notes","smsNotification":"N","productExpiryDate":null,"productDeleted":null,"alertExpiryDate":null,"idsku":"IDSKU1"},{"productId":5,"sku":"QTY","vendorProductId":"v1","productName":"P3name","productDescription":"p1 desc","supplierId":"s1","categoryId":"c","quantityPerUnit":1.0,"unitPrice":1.0,"msrp":1.0,"availableSize":40.0,"availableColors":"black,blue","size":40.0,"color":"white","discount":0.0,"unitWeight":1.0,"unitsInStock":1000.0,"unitsOnOrder":500.0,"reorderLevel":150.0,"productAvailable":"Y","discountAvailable":"N","currentOrder":0.0,"pictureURL":"Picture path","ranking":10,"note":"Sample Notes","smsNotification":"N","productExpiryDate":null,"productDeleted":null,"alertExpiryDate":null,"idsku":"IDSKU1"},{"productId":6,"sku":"QTY","vendorProductId":"v1","productName":"P4name","productDescription":"p1 desc","supplierId":"s1","categoryId":"c","quantityPerUnit":1.0,"unitPrice":1.0,"msrp":1.0,"availableSize":40.0,"availableColors":"black,blue","size":40.0,"color":"white","discount":0.0,"unitWeight":1.0,"unitsInStock":1000.0,"unitsOnOrder":500.0,"reorderLevel":150.0,"productAvailable":"Y","discountAvailable":"N","currentOrder":0.0,"pictureURL":"Picture path","ranking":10,"note":"Sample Notes","smsNotification":"N","productExpiryDate":null,"productDeleted":null,"alertExpiryDate":null,"idsku":"IDSKU1"},{"productId":7,"sku":"QTY","vendorProductId":"v1","productName":"P5name","productDescription":"p1 desc","supplierId":"s1","categoryId":"c","quantityPerUnit":1.0,"unitPrice":1.0,"msrp":1.0,"availableSize":40.0,"availableColors":"black,blue","size":40.0,"color":"white","discount":0.0,"unitWeight":1.0,"unitsInStock":1000.0,"unitsOnOrder":500.0,"reorderLevel":150.0,"productAvailable":"Y","discountAvailable":"N","currentOrder":0.0,"pictureURL":"Picture path","ranking":10,"note":"Sample Notes","smsNotification":"N","productExpiryDate":null,"productDeleted":null,"alertExpiryDate":null,"idsku":"IDSKU1"},{"productId":8,"sku":"QTY","vendorProductId":"v1","productName":"P6name","productDescription":"p1 desc","supplierId":"s1","categoryId":"c","quantityPerUnit":1.0,"unitPrice":1.0,"msrp":1.0,"availableSize":40.0,"availableColors":"black,blue","size":40.0,"color":"white","discount":0.0,"unitWeight":1.0,"unitsInStock":1000.0,"unitsOnOrder":500.0,"reorderLevel":150.0,"productAvailable":"Y","discountAvailable":"N","currentOrder":0.0,"pictureURL":"Picture path","ranking":10,"note":"Sample Notes","smsNotification":"N","productExpiryDate":null,"productDeleted":null,"alertExpiryDate":null,"idsku":"IDSKU1"},{"productId":9,"sku":"QTY","vendorProductId":"v1","productName":"P7name","productDescription":"p1 desc","supplierId":"s1","categoryId":"c","quantityPerUnit":1.0,"unitPrice":1.0,"msrp":1.0,"availableSize":40.0,"availableColors":"black,blue","size":40.0,"color":"white","discount":0.0,"unitWeight":1.0,"unitsInStock":1000.0,"unitsOnOrder":500.0,"reorderLevel":150.0,"productAvailable":"Y","discountAvailable":"N","currentOrder":0.0,"pictureURL":"Picture path","ranking":10,"note":"Sample Notes","smsNotification":"N","productExpiryDate":null,"productDeleted":null,"alertExpiryDate":null,"idsku":"IDSKU1"},{"productId":10,"sku":"QTY","vendorProductId":"v1","productName":"P8name","productDescription":"p1 desc","supplierId":"s1","categoryId":"c","quantityPerUnit":1.0,"unitPrice":1.0,"msrp":1.0,"availableSize":40.0,"availableColors":"black,blue","size":40.0,"color":"white","discount":0.0,"unitWeight":1.0,"unitsInStock":1000.0,"unitsOnOrder":500.0,"reorderLevel":150.0,"productAvailable":"Y","discountAvailable":"N","currentOrder":0.0,"pictureURL":"Picture path","ranking":10,"note":"Sample Notes","smsNotification":"N","productExpiryDate":null,"productDeleted":null,"alertExpiryDate":null,"idsku":"IDSKU1"},{"productId":11,"sku":"QTY","vendorProductId":"v1","productName":"P9name","productDescription":"p1 desc","supplierId":"s1","categoryId":"c","quantityPerUnit":1.0,"unitPrice":1.0,"msrp":1.0,"availableSize":40.0,"availableColors":"black,blue","size":40.0,"color":"white","discount":0.0,"unitWeight":1.0,"unitsInStock":1000.0,"unitsOnOrder":500.0,"reorderLevel":150.0,"productAvailable":"Y","discountAvailable":"N","currentOrder":0.0,"pictureURL":"Picture path","ranking":10,"note":"Sample Notes","smsNotification":"N","productExpiryDate":null,"productDeleted":null,"alertExpiryDate":null,"idsku":"IDSKU1"},{"productId":12,"sku":"QTY","vendorProductId":"v1","productName":"P9name","productDescription":"p1 desc","supplierId":"s1","categoryId":"c","quantityPerUnit":1.0,"unitPrice":1.0,"msrp":1.0,"availableSize":40.0,"availableColors":"black,blue","size":40.0,"color":"white","discount":0.0,"unitWeight":1.0,"unitsInStock":1000.0,"unitsOnOrder":500.0,"reorderLevel":150.0,"productAvailable":"Y","discountAvailable":"N","currentOrder":0.0,"pictureURL":"Picture path","ranking":10,"note":"Sample Notes","smsNotification":"N","productExpiryDate":null,"productDeleted":null,"alertExpiryDate":null,"idsku":"IDSKU1"},{"productId":13,"sku":"QTY","vendorProductId":"v1","productName":"P9name","productDescription":"p1 desc","supplierId":"s1","categoryId":"c","quantityPerUnit":1.0,"unitPrice":1.0,"msrp":1.0,"availableSize":40.0,"availableColors":"black,blue","size":40.0,"color":"white","discount":0.0,"unitWeight":1.0,"unitsInStock":1000.0,"unitsOnOrder":500.0,"reorderLevel":150.0,"productAvailable":"Y","discountAvailable":"N","currentOrder":0.0,"pictureURL":"Picture path","ranking":10,"note":"Sample Notes","smsNotification":"N","productExpiryDate":null,"productDeleted":null,"alertExpiryDate":null,"idsku":"IDSKU1"},{"productId":14,"sku":"QTY","vendorProductId":"v1","productName":"P9name","productDescription":"p1 desc","supplierId":"s1","categoryId":"c","quantityPerUnit":1.0,"unitPrice":1.0,"msrp":1.0,"availableSize":40.0,"availableColors":"black,blue","size":40.0,"color":"white","discount":0.0,"unitWeight":1.0,"unitsInStock":1000.0,"unitsOnOrder":500.0,"reorderLevel":150.0,"productAvailable":"Y","discountAvailable":"N","currentOrder":0.0,"pictureURL":"Picture path","ranking":10,"note":"Sample Notes","smsNotification":"N","productExpiryDate":null,"productDeleted":null,"alertExpiryDate":null,"idsku":"IDSKU1"},{"productId":15,"sku":"QTY","vendorProductId":"v1","productName":"P9name","productDescription":"p1 desc","supplierId":"s1","categoryId":"c","quantityPerUnit":1.0,"unitPrice":1.0,"msrp":1.0,"availableSize":40.0,"availableColors":"black,blue","size":40.0,"color":"white","discount":0.0,"unitWeight":1.0,"unitsInStock":1000.0,"unitsOnOrder":500.0,"reorderLevel":150.0,"productAvailable":"Y","discountAvailable":"N","currentOrder":0.0,"pictureURL":"Picture path","ranking":10,"note":"Sample Notes","smsNotification":"N","productExpiryDate":null,"productDeleted":null,"alertExpiryDate":null,"idsku":"IDSKU1"},{"productId":16,"sku":"QTY","vendorProductId":"v1","productName":"P10name","productDescription":"p1 desc","supplierId":"s1","categoryId":"c","quantityPerUnit":1.0,"unitPrice":1.0,"msrp":1.0,"availableSize":40.0,"availableColors":"black,blue","size":40.0,"color":"white","discount":0.0,"unitWeight":1.0,"unitsInStock":1000.0,"unitsOnOrder":500.0,"reorderLevel":150.0,"productAvailable":"Y","discountAvailable":"N","currentOrder":0.0,"pictureURL":"Picture path","ranking":10,"note":"Sample Notes","smsNotification":"N","productExpiryDate":null,"productDeleted":null,"alertExpiryDate":null,"idsku":"IDSKU1"}]

Answer 1

您可以使用 indexOf 和 length:

实现您自己的字符串比较方法

String.prototype.equals = function (str2) {
    return this.indexOf(str2) == 0 && this.length == str2.length;
}

或更 "PHP" 风格的方法：

function string_compare (str1, str2) {
   return str1.indexOf(str2) == 0 && str1.length == str2.length;
}

Answer 2

JS字符串比较是区分大小写的，你可能需要不区分大小写的，例如：

tempProductName.toUpperCase() === value.toUpperCase()

而不是：

tempProductName.toString() === value.toString()

无论如何你不需要toString()，因为该字段已经是一个字符串。

Answer 3

查看您的代码，这应该可以。

尝试更改迭代器 - for..in 用于迭代对象（即字典）。要遍历数组，请使用常规 for 或 forEach:

function searchProduct(value) {
  allProducts
    .filter(function(product) {
      return product[productName] === value
    })
    .forEach(function(product) {
      $('#description').val(product.productDescription);
      $('.cost').val(product.unitPrice);
    });
}

比较两个字符串在 javascript 中无法正常工作

Compare two strings is not working properly in javascript

javascript

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